AWS Certified Developer Associate Practice Exam

Exam Name DVA-C02 Practice Exam – AWS Certified Developer Associate (2026 Updated)
Exam Provider Amazon Web Services (AWS)
Certification Type Associate-Level Certification (Application Development & Deployment on AWS)
Total Practice Questions 150 Advanced MCQs (Scenario-Based + Lambda + API Gateway + CI/CD + Debugging)
Exam Domains Covered • Development with AWS Services (Lambda, DynamoDB, API Gateway, S3)
• Security (IAM, Cognito, KMS, Secrets Manager)
• Deployment (CodePipeline, CodeBuild, CodeDeploy, CloudFormation)
• Troubleshooting & Optimization (CloudWatch, X-Ray, Logging)
• Event-Driven Architecture (SQS, SNS, EventBridge, Kinesis)
Questions in Real Exam • Total: ~65 Questions
• Scenario-driven with real-world application development cases
• Focus on debugging, deployment strategies, and AWS service integration
Exam Duration • Total Time: 130 Minutes
• Moderate-to-fast pace with applied reasoning questions
• Requires hands-on AWS development experience
Passing Score • Scaled Score: 720 / 1000
• Requires strong understanding of AWS development practices
• Emphasis on practical problem-solving and debugging
Question Format • Multiple Choice & Multiple Response
• Scenario-Based Coding & Architecture Questions
• CI/CD & Deployment Cases
• Debugging & Performance Optimization
• Security & Access Control Scenarios
Difficulty Level Intermediate to Advanced (Hands-On Development + Scenario Thinking)
Key Knowledge Areas • Serverless development (Lambda, API Gateway, Step Functions)
• Event-driven architecture (SNS, SQS, EventBridge, Kinesis)
• CI/CD pipelines (CodePipeline, CodeBuild, CodeDeploy)
• Security (IAM roles, Cognito authentication, KMS encryption)
• Monitoring & debugging (CloudWatch, X-Ray, Logs Insights)
• Data storage (DynamoDB, S3, RDS)
Common Exam Traps • Confusing SNS vs SQS (pub/sub vs queue)
• Ignoring Lambda retries and idempotency issues
• Misconfiguring IAM roles and permissions
• Overusing EC2 instead of serverless services
• Missing API Gateway throttling and caching features
• Not handling DLQs for failed events
• Choosing wrong database type (DynamoDB vs RDS)
Skills Developed • Building scalable serverless applications
• Designing event-driven architectures
• Implementing secure AWS applications
• Automating deployments with CI/CD pipelines
• Debugging distributed systems
• Optimizing application performance and cost
Study Strategy • Focus on Lambda + API Gateway integration scenarios
• Practice event-driven design patterns deeply
• Learn CI/CD pipelines (CodePipeline, CodeBuild, CodeDeploy)
• Understand IAM roles and permission boundaries
• Use CloudWatch and X-Ray for debugging practice
• Take full-length timed mock exams
• Review explanations to identify hidden exam traps
Best For • Software developers working with AWS
• Backend engineers building cloud-native apps
• DevOps engineers handling CI/CD pipelines
• Professionals transitioning into AWS development roles
Career Benefits • Validates real-world AWS development skills
• Opens roles in backend development and cloud engineering
• Enhances knowledge of serverless and event-driven systems
• Increases earning potential in cloud development roles
• Builds strong foundation for professional-level AWS certifications
Updated 2026 Latest Version – Based on AWS DVA-C02 Exam Guide & Real Exam Patterns

1.

A developer wants to run code without managing servers. What is BEST?

A. EC2
B. Lambda
C. RDS
D. EBS

Answer: B
Rationale: AWS Lambda allows developers to run code without provisioning or managing servers. It automatically scales based on demand and charges only for execution time, making it ideal for event-driven architectures.


2.

A developer needs to store application data as key-value pairs. What is BEST?

A. RDS
B. DynamoDB
C. S3
D. EBS

Answer: B
Rationale: DynamoDB is a fully managed NoSQL database designed for key-value and document storage with low latency and automatic scaling.


3.

A developer wants to trigger code when an S3 object is uploaded. What is BEST?

A. EC2
B. Lambda with S3 event
C. RDS
D. EBS

Answer: B
Rationale: S3 event notifications can trigger Lambda functions, enabling event-driven processing.


4.

A developer wants to expose APIs for a serverless application. What is BEST?

A. EC2
B. API Gateway
C. S3
D. EBS

Answer: B
Rationale: API Gateway allows developers to create, publish, and manage APIs.


5.

A developer wants to deploy code automatically. What is BEST?

A. CodeDeploy
B. EC2
C. S3
D. RDS

Answer: A
Rationale: CodeDeploy automates deployments across services.


6.

A developer wants continuous integration. What is BEST?

A. CodeBuild
B. EC2
C. S3
D. RDS

Answer: A
Rationale: CodeBuild compiles and tests code.


7.

A developer wants to manage application secrets. What is BEST?

A. S3
B. Secrets Manager
C. CloudWatch
D. Lambda

Answer: B
Rationale: Secrets Manager securely stores and rotates secrets.


8.

A developer needs to cache frequently accessed data. What is BEST?

A. RDS
B. ElastiCache
C. DynamoDB
D. S3

Answer: B
Rationale: ElastiCache improves performance.


9.

A developer wants to log application activity. What is BEST?

A. CloudTrail
B. CloudWatch Logs
C. Config
D. Lambda

Answer: B
Rationale: CloudWatch Logs stores application logs.


10.

A developer wants to track API calls. What is BEST?

A. CloudTrail
B. CloudWatch
C. Config
D. Lambda

Answer: A
Rationale: CloudTrail logs API calls.


11.

A developer wants to use environment variables in Lambda. What is BEST?

A. Store in code
B. Use environment variables
C. Use S3
D. Use RDS

Answer: B
Rationale: Environment variables provide configuration without changing code.


12.

A developer wants to decouple application components. What is BEST?

A. SNS
B. SQS
C. Lambda
D. EC2

Answer: B
Rationale: SQS decouples components.


13.

A developer wants pub/sub messaging. What is BEST?

A. SNS
B. SQS
C. Lambda
D. EC2

Answer: A
Rationale: SNS provides pub/sub.


14.

A developer wants to deploy infrastructure as code. What is BEST?

A. CloudFormation
B. EC2
C. S3
D. RDS

Answer: A
Rationale: CloudFormation enables IaC.


15.

A developer wants to manage access securely. What is BEST?

A. IAM
B. CloudTrail
C. Config
D. Lambda

Answer: A
Rationale: IAM manages access control.


16.

A developer wants to store static content. What is BEST?

A. S3
B. EC2
C. RDS
D. DynamoDB

Answer: A
Rationale: S3 stores static files.


17.

A developer wants serverless workflows. What is BEST?

A. Step Functions
B. EC2
C. S3
D. RDS

Answer: A
Rationale: Step Functions orchestrate workflows.


18.

A developer wants to containerize applications. What is BEST?

A. ECS
B. EC2
C. S3
D. RDS

Answer: A
Rationale: ECS runs containers.


19.

A developer wants serverless containers. What is BEST?

A. ECS
B. Fargate
C. EC2
D. Lambda

Answer: B
Rationale: Fargate runs containers without servers.


20.

A developer wants to store files for backup. What is BEST?

A. S3
B. EBS
C. EC2
D. RDS

Answer: A
Rationale: S3 is ideal for backups.


21.

A developer wants to monitor application metrics. What is BEST?

A. CloudWatch
B. CloudTrail
C. Config
D. Lambda

Answer: A
Rationale: CloudWatch monitors metrics.


22.

A developer wants to build CI/CD pipeline. What is BEST?

A. CodePipeline
B. EC2
C. S3
D. RDS

Answer: A
Rationale: CodePipeline automates CI/CD.


23.

A developer wants to analyze logs. What is BEST?

A. CloudWatch Logs Insights
B. CloudTrail
C. Config
D. Lambda

Answer: A
Rationale: Logs Insights enables log queries.


24.

A developer wants to secure APIs. What is BEST?

A. IAM roles
B. API Gateway + authorizer
C. S3
D. EC2

Answer: B
Rationale: API Gateway authorizers secure APIs.


25.

A developer wants to use NoSQL DB. What is BEST?

A. RDS
B. DynamoDB
C. Redshift
D. S3

Answer: B
Rationale: DynamoDB is NoSQL.


26.

A developer wants event-driven architecture. What is BEST?

A. Lambda
B. EC2
C. RDS
D. EBS

Answer: A
Rationale: Lambda supports event-driven design.


27.

A developer wants to scale automatically. What is BEST?

A. Auto Scaling
B. EC2 manual
C. S3
D. RDS

Answer: A
Rationale: Auto Scaling adjusts capacity.


28.

A developer wants to deploy serverless APIs. What is BEST?

A. API Gateway + Lambda
B. EC2
C. S3
D. RDS

Answer: A
Rationale: API Gateway + Lambda enables serverless APIs.


29.

A developer wants to encrypt data at rest. What is BEST?

A. IAM
B. KMS
C. CloudWatch
D. Lambda

Answer: B
Rationale: KMS manages encryption keys.


30.

A developer wants to automate deployments. What is BEST?

A. CodeDeploy
B. EC2
C. S3
D. RDS

Answer: A
Rationale: CodeDeploy automates deployments.

31.

A Lambda function times out during heavy processing. What is the BEST solution?

A. Increase memory and timeout
B. Use S3
C. Use RDS
D. Use EC2

Answer: A
Rationale: Increasing memory also increases CPU allocation in Lambda, improving execution speed. Extending timeout ensures long-running tasks complete without premature termination.


32.

A developer wants to ensure idempotent Lambda processing. What is BEST?

A. Ignore duplicates
B. Use unique request IDs and deduplication logic
C. Use EC2
D. Use RDS

Answer: B
Rationale: Idempotency ensures repeated executions do not produce duplicate results. Using unique identifiers and conditional writes prevents duplicate processing in retry scenarios.


33.

A developer needs asynchronous processing between services. What is BEST?

A. SNS + SQS
B. EC2
C. RDS
D. S3

Answer: A
Rationale: SNS provides pub/sub messaging, while SQS queues messages for asynchronous processing, decoupling components and improving scalability and fault tolerance.


34.

A Lambda function must access a DynamoDB table securely. What is BEST?

A. Hardcode credentials
B. IAM role attached to Lambda
C. Store credentials in code
D. Use EC2

Answer: B
Rationale: IAM roles provide secure, temporary credentials without embedding secrets, following AWS security best practices.


35.

A developer wants to reduce cold starts in Lambda. What is BEST?

A. Increase memory
B. Provisioned concurrency
C. Use EC2
D. Use S3

Answer: B
Rationale: Provisioned concurrency keeps Lambda instances warm, eliminating cold start latency for critical applications.


36.

A developer wants to trigger a workflow after multiple Lambda steps. What is BEST?

A. Step Functions
B. EC2
C. S3
D. RDS

Answer: A
Rationale: Step Functions orchestrate multiple Lambda functions with state management, retries, and branching logic.


37.

A developer needs to store secrets securely for an app. What is BEST?

A. S3
B. Secrets Manager
C. CloudWatch
D. Lambda

Answer: B
Rationale: Secrets Manager securely stores and rotates secrets with encryption.


38.

A developer wants to monitor Lambda errors. What is BEST?

A. CloudTrail
B. CloudWatch Logs and alarms
C. Config
D. Lambda

Answer: B
Rationale: CloudWatch logs capture errors, and alarms notify developers when thresholds are exceeded.


39.

A developer wants to deploy code automatically after commit. What is BEST?

A. CodePipeline
B. EC2
C. S3
D. RDS

Answer: A
Rationale: CodePipeline automates CI/CD workflows.


40.

A developer wants to test code in isolation. What is BEST?

A. Unit tests in CodeBuild
B. EC2
C. S3
D. RDS

Answer: A
Rationale: CodeBuild runs automated tests.


41.

A developer needs API authentication. What is BEST?

A. IAM
B. API Gateway authorizer
C. S3
D. EC2

Answer: B
Rationale: API Gateway authorizers provide authentication and authorization.


42.

A developer wants caching for API responses. What is BEST?

A. DynamoDB
B. API Gateway caching
C. EC2
D. RDS

Answer: B
Rationale: API Gateway caching reduces backend load.


43.

A developer wants to decouple microservices. What is BEST?

A. SQS
B. EC2
C. RDS
D. S3

Answer: A
Rationale: SQS enables decoupling.


44.

A developer wants pub/sub messaging. What is BEST?

A. SNS
B. SQS
C. Lambda
D. EC2

Answer: A
Rationale: SNS provides pub/sub.


45.

A developer wants to log API activity. What is BEST?

A. CloudTrail
B. CloudWatch
C. Config
D. Lambda

Answer: A
Rationale: CloudTrail logs API calls.


46.

A developer needs to encrypt environment variables. What is BEST?

A. IAM
B. KMS
C. CloudWatch
D. Lambda

Answer: B
Rationale: KMS encrypts sensitive data.


47.

A developer wants to process messages reliably. What is BEST?

A. SQS with DLQ
B. EC2
C. RDS
D. S3

Answer: A
Rationale: Dead-letter queues handle failed messages.


48.

A developer wants to retry failed events automatically. What is BEST?

A. Lambda retries + DLQ
B. EC2
C. RDS
D. S3

Answer: A
Rationale: Lambda retries and DLQ handle failures.


49.

A developer wants to deploy infrastructure. What is BEST?

A. CloudFormation
B. EC2
C. S3
D. RDS

Answer: A
Rationale: CloudFormation enables IaC.


50.

A developer wants to containerize apps. What is BEST?

A. ECS
B. EC2
C. S3
D. RDS

Answer: A
Rationale: ECS runs containers.


51.

A developer wants serverless containers. What is BEST?

A. ECS
B. Fargate
C. EC2
D. Lambda

Answer: B
Rationale: Fargate removes server management.


52.

A developer wants event-driven pipelines. What is BEST?

A. EventBridge
B. EC2
C. S3
D. RDS

Answer: A
Rationale: EventBridge triggers events.


53.

A developer needs file storage. What is BEST?

A. S3
B. EC2
C. RDS
D. DynamoDB

Answer: A
Rationale: S3 stores files.


54.

A developer wants NoSQL DB. What is BEST?

A. RDS
B. DynamoDB
C. Redshift
D. S3

Answer: B
Rationale: DynamoDB is NoSQL.


55.

A developer wants relational DB. What is BEST?

A. RDS
B. DynamoDB
C. Redshift
D. S3

Answer: A
Rationale: RDS is relational.


56.

A developer wants analytics. What is BEST?

A. Redshift
B. DynamoDB
C. RDS
D. EC2

Answer: A
Rationale: Redshift is analytics.


57.

A developer wants monitoring. What is BEST?

A. CloudWatch
B. CloudTrail
C. Config
D. Lambda

Answer: A
Rationale: CloudWatch monitors.


58.

A developer wants CI/CD pipeline. What is BEST?

A. CodePipeline
B. EC2
C. S3
D. RDS

Answer: A
Rationale: CodePipeline automates CI/CD.


59.

A developer wants to debug logs. What is BEST?

A. CloudWatch Logs Insights
B. CloudTrail
C. Config
D. Lambda

Answer: A
Rationale: Logs Insights analyzes logs.


60.

A developer wants serverless architecture. What is BEST?

A. Lambda + API Gateway
B. EC2
C. S3
D. RDS

Answer: A
Rationale: Serverless reduces operational overhead.

61.

A Lambda function processing SQS messages is failing repeatedly. What is the BEST solution?

A. Increase memory
B. Configure a Dead Letter Queue (DLQ)
C. Use EC2
D. Use S3

Answer: B
Rationale: A DLQ ensures failed messages are not lost and can be analyzed later. Without a DLQ, messages may be retried indefinitely or discarded, making debugging difficult and risking data loss in production systems.


62.

A developer wants to ensure secure API access using JWT tokens. What is BEST?

A. IAM only
B. API Gateway Lambda authorizer
C. S3
D. EC2

Answer: B
Rationale: Lambda authorizers validate JWT tokens and provide fine-grained access control. This allows secure authentication and authorization for APIs while integrating with identity providers.


63.

A Lambda function must process events in order. What is BEST?

A. SNS
B. SQS FIFO queue
C. S3
D. DynamoDB

Answer: B
Rationale: SQS FIFO queues guarantee message ordering and exactly-once processing. This is critical when sequence matters, such as financial transactions or ordered event processing pipelines.


64.

A developer wants to cache frequently accessed DynamoDB data. What is BEST?

A. S3
B. ElastiCache
C. RDS
D. EC2

Answer: B
Rationale: ElastiCache stores frequently accessed data in memory, reducing DynamoDB read load and improving latency significantly, which is essential for high-performance applications.


65.

A Lambda function needs to access resources in a VPC. What is required?

A. Nothing
B. Configure VPC settings in Lambda
C. Use S3
D. Use RDS

Answer: B
Rationale: Lambda must be configured with VPC subnets and security groups to access private resources such as RDS databases, otherwise it cannot reach internal endpoints.


66.

A developer wants to automate deployments with rollback support. What is BEST?

A. CodeDeploy
B. EC2
C. S3
D. RDS

Answer: A
Rationale: CodeDeploy supports automated deployments with rollback capabilities in case of failures, ensuring application stability and minimizing downtime during releases.


67.

A developer needs to monitor API latency. What is BEST?

A. CloudTrail
B. CloudWatch metrics
C. Config
D. Lambda

Answer: B
Rationale: CloudWatch provides latency metrics and dashboards, enabling performance monitoring and alerting for APIs in real time.


68.

A developer wants to retry failed Lambda executions asynchronously. What is BEST?

A. Manual retry
B. Configure Lambda retry behavior
C. Use EC2
D. Use S3

Answer: B
Rationale: Lambda automatically retries asynchronous invocations. Configuring retry settings ensures failed executions are retried before being sent to a DLQ.


69.

A developer needs to store application configuration securely. What is BEST?

A. Hardcode values
B. Systems Manager Parameter Store
C. S3
D. EC2

Answer: B
Rationale: Parameter Store securely stores configuration values and integrates with IAM and KMS for encryption, avoiding hardcoding sensitive data.


70.

A developer wants to decouple services with guaranteed delivery. What is BEST?

A. SNS
B. SQS
C. Lambda
D. EC2

Answer: B
Rationale: SQS ensures message durability and reliable delivery, making it ideal for decoupled architectures where messages must not be lost.


71.

A developer wants to deploy multiple services together. What is BEST?

A. CloudFormation
B. EC2
C. S3
D. RDS

Answer: A
Rationale: CloudFormation enables infrastructure as code, allowing multiple resources to be deployed consistently and reproducibly.


72.

A developer wants to trigger workflows based on events. What is BEST?

A. EventBridge
B. EC2
C. S3
D. RDS

Answer: A
Rationale: EventBridge routes events between services and triggers workflows, enabling event-driven architectures.


73.

A developer needs to debug Lambda performance issues. What is BEST?

A. CloudTrail
B. CloudWatch Logs and X-Ray
C. Config
D. S3

Answer: B
Rationale: AWS X-Ray traces requests across services, while CloudWatch logs provide execution details, enabling deep debugging of performance bottlenecks.


74.

A developer wants to reduce DynamoDB read costs. What is BEST?

A. Increase capacity
B. Use DAX caching
C. Use EC2
D. Use S3

Answer: B
Rationale: DynamoDB Accelerator (DAX) provides in-memory caching, reducing read operations and costs while improving performance.


75.

A developer needs to enforce least privilege access. What is BEST?

A. Full access policies
B. IAM policies with minimal permissions
C. S3
D. EC2

Answer: B
Rationale: Least privilege ensures users and services have only the permissions they need, reducing security risks and preventing accidental misuse.


76.

A developer wants to version application code deployments. What is BEST?

A. Lambda versions and aliases
B. EC2
C. S3
D. RDS

Answer: A
Rationale: Lambda versions and aliases allow controlled deployments and traffic shifting, enabling safe releases and rollbacks.


77.

A developer wants blue/green deployments. What is BEST?

A. CodeDeploy
B. EC2
C. S3
D. RDS

Answer: A
Rationale: CodeDeploy supports blue/green deployments, allowing traffic shifting between versions with minimal downtime.


78.

A developer needs API throttling. What is BEST?

A. API Gateway throttling
B. EC2
C. S3
D. RDS

Answer: A
Rationale: API Gateway throttling protects backend systems by limiting request rates, preventing overload and ensuring stability.


79.

A developer wants secure file uploads. What is BEST?

A. Public S3
B. Pre-signed URLs
C. EC2
D. RDS

Answer: B
Rationale: Pre-signed URLs allow secure, temporary access to S3 for uploads without exposing credentials.


80.

A developer needs to process large files asynchronously. What is BEST?

A. Lambda + S3 events
B. EC2
C. RDS
D. DynamoDB

Answer: A
Rationale: S3 events trigger Lambda for asynchronous processing, enabling scalable handling of large file uploads.


81.

A developer wants to monitor errors in production. What is BEST?

A. CloudTrail
B. CloudWatch alarms
C. Config
D. S3

Answer: B
Rationale: CloudWatch alarms notify developers when errors exceed thresholds, enabling proactive monitoring and faster incident response.


82.

A developer needs to manage API keys. What is BEST?

A. IAM
B. API Gateway API keys
C. S3
D. EC2

Answer: B
Rationale: API Gateway manages API keys and usage plans, controlling access and rate limits for APIs.


83.

A developer wants event filtering. What is BEST?

A. EventBridge rules
B. EC2
C. S3
D. RDS

Answer: A
Rationale: EventBridge rules filter and route events based on patterns, enabling flexible event-driven architectures.


84.

A developer needs to process high-throughput events. What is BEST?

A. SNS
B. Kinesis
C. Lambda
D. EC2

Answer: B
Rationale: Kinesis handles high-throughput streaming data with scalability and low latency.


85.

A developer wants to store session data. What is BEST?

A. DynamoDB
B. RDS
C. S3
D. EC2

Answer: A
Rationale: DynamoDB provides low-latency storage for session data and scales automatically.


86.

A developer wants to secure Lambda environment variables. What is BEST?

A. Plain text
B. KMS encryption
C. S3
D. EC2

Answer: B
Rationale: KMS encrypts environment variables, ensuring sensitive data is protected.


87.

A developer wants to trace distributed requests. What is BEST?

A. CloudTrail
B. X-Ray
C. Config
D. S3

Answer: B
Rationale: AWS X-Ray traces requests across services, helping debug distributed applications.


88.

A developer wants to automate builds. What is BEST?

A. CodeBuild
B. EC2
C. S3
D. RDS

Answer: A
Rationale: CodeBuild automates building and testing code.


89.

A developer wants centralized logging. What is BEST?

A. CloudWatch Logs
B. CloudTrail
C. Config
D. Lambda

Answer: A
Rationale: CloudWatch Logs centralizes logs for monitoring and troubleshooting.


90.

A developer wants serverless backend. What is BEST?

A. Lambda + API Gateway
B. EC2
C. S3
D. RDS

Answer: A
Rationale: Lambda and API Gateway provide fully serverless backend infrastructure, reducing operational overhead and enabling scalability.

91.

A Lambda function is throttled due to high concurrency. What is the BEST solution?

A. Increase timeout
B. Increase reserved concurrency
C. Use S3
D. Use RDS

Answer: B
Rationale: Reserved concurrency increases the number of concurrent executions allowed for a Lambda function, preventing throttling during peak traffic while ensuring predictable scaling.


92.

A developer wants to limit API usage per client. What is BEST?

A. IAM
B. API Gateway usage plans
C. S3
D. EC2

Answer: B
Rationale: Usage plans enforce quotas and throttling per API key, allowing fine-grained control over client consumption and protecting backend resources from abuse.


93.

A developer needs guaranteed message delivery with ordering. What is BEST?

A. SNS
B. SQS FIFO
C. Lambda
D. EC2

Answer: B
Rationale: SQS FIFO queues ensure ordered message delivery and exactly-once processing, making them ideal for workflows requiring strict sequencing and reliability.


94.

A developer wants to debug distributed microservices. What is BEST?

A. CloudTrail
B. X-Ray
C. Config
D. S3

Answer: B
Rationale: AWS X-Ray provides end-to-end tracing across services, helping identify latency issues, bottlenecks, and failures in distributed architectures.


95.

A Lambda function fails intermittently due to external API issues. What is BEST?

A. Ignore failures
B. Implement retries with exponential backoff
C. Use EC2
D. Use S3

Answer: B
Rationale: Exponential backoff reduces load on failing services and improves reliability by spacing retries, preventing cascading failures.


96.

A developer wants zero-downtime deployments. What is BEST?

A. Manual deployment
B. Blue/green deployment with CodeDeploy
C. EC2
D. S3

Answer: B
Rationale: Blue/green deployments shift traffic gradually, enabling safe releases and rollback without downtime.


97.

A developer needs secure API authentication with OAuth. What is BEST?

A. IAM
B. API Gateway + Cognito
C. S3
D. EC2

Answer: B
Rationale: Cognito integrates with API Gateway to provide OAuth-based authentication and user management.


98.

A developer wants to encrypt data in transit. What is BEST?

A. IAM
B. TLS/HTTPS
C. S3
D. EC2

Answer: B
Rationale: TLS/HTTPS ensures encryption during data transmission, protecting against interception and man-in-the-middle attacks.


99.

A developer needs to handle duplicate events. What is BEST?

A. Ignore duplicates
B. Idempotent processing
C. Use EC2
D. Use S3

Answer: B
Rationale: Idempotency ensures repeated processing produces the same result, preventing duplicate data issues.


100.

A developer wants to store large files efficiently. What is BEST?

A. DynamoDB
B. S3
C. RDS
D. EC2

Answer: B
Rationale: S3 provides scalable, durable storage for large objects.


101.

A developer wants to monitor API errors. What is BEST?

A. CloudTrail
B. CloudWatch metrics and alarms
C. Config
D. Lambda

Answer: B
Rationale: CloudWatch provides real-time monitoring and alerting.


102.

A developer needs to manage infrastructure changes safely. What is BEST?

A. Manual changes
B. CloudFormation change sets
C. EC2
D. S3

Answer: B
Rationale: Change sets preview infrastructure changes before execution, reducing risk.


103.

A developer wants event-driven architecture. What is BEST?

A. EventBridge
B. EC2
C. RDS
D. S3

Answer: A
Rationale: EventBridge enables event-driven workflows.


104.

A developer needs high-throughput event ingestion. What is BEST?

A. SNS
B. Kinesis
C. Lambda
D. EC2

Answer: B
Rationale: Kinesis handles high-throughput streaming data.


105.

A developer wants to secure secrets in code. What is BEST?

A. Hardcode
B. Secrets Manager
C. S3
D. EC2

Answer: B
Rationale: Secrets Manager securely stores sensitive data.


106.

A developer needs reliable message processing. What is BEST?

A. SNS
B. SQS with DLQ
C. Lambda
D. EC2

Answer: B
Rationale: DLQ captures failed messages for analysis.


107.

A developer wants to reduce latency. What is BEST?

A. Increase memory
B. Use caching
C. Use EC2
D. Use S3

Answer: B
Rationale: Caching reduces response time and backend load.


108.

A developer wants to deploy microservices. What is BEST?

A. ECS
B. EC2
C. S3
D. RDS

Answer: A
Rationale: ECS manages containers for microservices.


109.

A developer wants serverless containers. What is BEST?

A. ECS
B. Fargate
C. EC2
D. Lambda

Answer: B
Rationale: Fargate removes server management.


110.

A developer wants API caching. What is BEST?

A. API Gateway cache
B. EC2
C. S3
D. RDS

Answer: A
Rationale: API Gateway caching reduces backend calls.


111.

A developer wants centralized logging. What is BEST?

A. CloudWatch Logs
B. CloudTrail
C. Config
D. Lambda

Answer: A
Rationale: CloudWatch Logs centralizes logs.


112.

A developer needs build automation. What is BEST?

A. CodeBuild
B. EC2
C. S3
D. RDS

Answer: A
Rationale: CodeBuild automates builds.


113.

A developer wants CI/CD pipeline. What is BEST?

A. CodePipeline
B. EC2
C. S3
D. RDS

Answer: A
Rationale: CodePipeline automates CI/CD.


114.

A developer needs API throttling. What is BEST?

A. API Gateway throttling
B. EC2
C. S3
D. RDS

Answer: A
Rationale: Throttling protects backend systems.


115.

A developer wants secure file upload. What is BEST?

A. Public S3
B. Pre-signed URLs
C. EC2
D. RDS

Answer: B
Rationale: Pre-signed URLs allow secure uploads.


116.

A developer needs retry logic. What is BEST?

A. Ignore errors
B. Exponential backoff
C. EC2
D. S3

Answer: B
Rationale: Backoff improves reliability.


117.

A developer wants distributed tracing. What is BEST?

A. CloudTrail
B. X-Ray
C. Config
D. S3

Answer: B
Rationale: X-Ray traces requests.


118.

A developer wants scalable DB. What is BEST?

A. DynamoDB
B. RDS
C. EC2
D. S3

Answer: A
Rationale: DynamoDB scales automatically.


119.

A developer needs relational DB. What is BEST?

A. RDS
B. DynamoDB
C. Redshift
D. S3

Answer: A
Rationale: RDS provides relational DB.


120.

A developer wants serverless backend. What is BEST?

A. Lambda + API Gateway
B. EC2
C. S3
D. RDS

Answer: A
Rationale: Serverless backend reduces operational overhead and scales automatically.

121.

A Lambda processing SQS batches fails for a few records only. What is BEST?

A. Retry entire batch
B. Enable partial batch response
C. Use EC2
D. Use S3

Answer: B
Rationale: Partial batch response lets Lambda acknowledge successful records while retrying only failed ones, reducing duplicate processing and improving efficiency for large batches.


122.

A developer wants to prevent one noisy Lambda from consuming all concurrency. What is BEST?

A. Increase timeout
B. Set reserved concurrency
C. Use S3
D. Use RDS

Answer: B
Rationale: Reserved concurrency limits the maximum concurrent executions for a function, protecting other functions from being throttled and ensuring fair resource allocation.


123.

A developer needs to restrict S3 access by IP. What is BEST?

A. IAM only
B. Bucket policy with condition
C. EC2
D. RDS

Answer: B
Rationale: Bucket policies with condition keys (like aws:SourceIp) allow restricting access based on IP address, improving security without changing application code.


124.

A Lambda must process high-throughput Kinesis data. What is BEST?

A. Single shard
B. Increase shards and parallelization
C. Use S3
D. Use RDS

Answer: B
Rationale: Increasing shard count and enabling parallelization improves throughput and processing speed for Kinesis-based Lambda consumers.


125.

A developer wants to secure API Gateway with IAM auth. What is BEST?

A. Public API
B. IAM authorization
C. S3
D. EC2

Answer: B
Rationale: IAM authorization ensures only authenticated AWS users can access APIs, providing fine-grained control via policies.


126.

A developer needs to rotate database credentials automatically. What is BEST?

A. Hardcode
B. Secrets Manager rotation
C. S3
D. EC2

Answer: B
Rationale: Secrets Manager supports automatic rotation of credentials, improving security and reducing manual effort.


127.

A Lambda function accesses DynamoDB frequently with low latency requirement. What is BEST?

A. RDS
B. DynamoDB with DAX
C. S3
D. EC2

Answer: B
Rationale: DynamoDB Accelerator (DAX) provides in-memory caching, reducing read latency and improving performance for high-read workloads.


128.

A developer needs to enforce HTTPS for S3 access. What is BEST?

A. IAM
B. Bucket policy condition
C. EC2
D. RDS

Answer: B
Rationale: Bucket policies can enforce secure transport using conditions like aws:SecureTransport, ensuring all requests use HTTPS.


129.

A developer wants canary deployments for Lambda. What is BEST?

A. Manual deploy
B. Lambda aliases with traffic shifting
C. EC2
D. S3

Answer: B
Rationale: Lambda aliases support weighted traffic shifting, enabling canary deployments and gradual rollouts with minimal risk.


130.

A developer needs to process duplicate events safely. What is BEST?

A. Ignore duplicates
B. Idempotent logic with unique keys
C. EC2
D. S3

Answer: B
Rationale: Idempotent logic ensures duplicate events do not cause inconsistent results, which is critical in distributed systems.


131.

A developer wants to throttle Lambda concurrency globally. What is BEST?

A. Increase memory
B. Account concurrency limit
C. S3
D. RDS

Answer: B
Rationale: Account-level concurrency limits control total Lambda executions across all functions, preventing resource exhaustion.


132.

A developer needs to debug API Gateway errors. What is BEST?

A. CloudTrail
B. CloudWatch logs and execution logs
C. Config
D. S3

Answer: B
Rationale: API Gateway integrates with CloudWatch for execution logs, helping identify request/response errors and latency issues.


133.

A developer wants secure temporary credentials. What is BEST?

A. Hardcode
B. STS tokens
C. S3
D. EC2

Answer: B
Rationale: AWS STS provides temporary credentials, improving security and reducing risk of long-term credential exposure.


134.

A developer wants event filtering for Lambda triggers. What is BEST?

A. EC2
B. EventBridge rules
C. S3
D. RDS

Answer: B
Rationale: EventBridge allows filtering events before invoking Lambda, reducing unnecessary executions and cost.


135.

A developer needs to ensure ordered processing in Kinesis. What is BEST?

A. Random partition key
B. Same partition key
C. S3
D. RDS

Answer: B
Rationale: Kinesis guarantees ordering per shard; using the same partition key ensures events are processed in sequence.


136.

A developer wants to secure environment variables. What is BEST?

A. Plain text
B. KMS encryption
C. S3
D. EC2

Answer: B
Rationale: KMS encrypts sensitive data in environment variables, ensuring security compliance.


137.

A developer needs to retry failed API calls. What is BEST?

A. Ignore
B. Exponential backoff
C. EC2
D. S3

Answer: B
Rationale: Backoff reduces system stress and improves success rates.


138.

A developer wants centralized metrics. What is BEST?

A. CloudWatch
B. CloudTrail
C. Config
D. Lambda

Answer: A
Rationale: CloudWatch aggregates metrics across services.


139.

A developer needs CI/CD rollback. What is BEST?

A. Manual rollback
B. CodeDeploy automatic rollback
C. EC2
D. S3

Answer: B
Rationale: CodeDeploy automatically rolls back failed deployments.


140.

A developer wants API authorization using Cognito. What is BEST?

A. IAM
B. Cognito authorizer
C. S3
D. EC2

Answer: B
Rationale: Cognito integrates with API Gateway for authentication.


141.

A developer wants high-throughput ingestion. What is BEST?

A. SNS
B. Kinesis
C. Lambda
D. EC2

Answer: B
Rationale: Kinesis handles streaming data at scale.


142.

A developer wants secure uploads. What is BEST?

A. Public S3
B. Pre-signed URLs
C. EC2
D. RDS

Answer: B
Rationale: Pre-signed URLs provide secure temporary access.


143.

A developer wants event-driven pipelines. What is BEST?

A. EventBridge
B. EC2
C. S3
D. RDS

Answer: A
Rationale: EventBridge enables event-driven workflows.


144.

A developer needs monitoring alerts. What is BEST?

A. CloudWatch alarms
B. CloudTrail
C. Config
D. Lambda

Answer: A
Rationale: CloudWatch alarms notify issues.


145.

A developer wants logging. What is BEST?

A. CloudWatch Logs
B. CloudTrail
C. Config
D. Lambda

Answer: A
Rationale: CloudWatch Logs centralizes logs.


146.

A developer needs build automation. What is BEST?

A. CodeBuild
B. EC2
C. S3
D. RDS

Answer: A
Rationale: CodeBuild automates builds.


147.

A developer wants pipeline automation. What is BEST?

A. CodePipeline
B. EC2
C. S3
D. RDS

Answer: A
Rationale: CodePipeline automates CI/CD.


148.

A developer wants scalable DB. What is BEST?

A. DynamoDB
B. RDS
C. EC2
D. S3

Answer: A
Rationale: DynamoDB scales automatically.


149.

A developer needs relational DB. What is BEST?

A. RDS
B. DynamoDB
C. Redshift
D. S3

Answer: A
Rationale: RDS provides relational database.


150.

A developer wants serverless backend. What is BEST?

A. Lambda + API Gateway
B. EC2
C. S3
D. RDS

Answer: A
Rationale: Serverless backend reduces operational overhead and scales automatically.