{"id":18790,"date":"2026-09-22T10:02:31","date_gmt":"2026-09-22T10:02:31","guid":{"rendered":"https:\/\/www.examlabs.com\/certification\/?p=18790"},"modified":"2026-09-22T10:02:31","modified_gmt":"2026-09-22T10:02:31","slug":"amazon-aws-certified-developer-associate-dva-c02-practice-test-questions-and-exam-dumps-part9-q161-180","status":"publish","type":"post","link":"https:\/\/www.examlabs.com\/certification\/amazon-aws-certified-developer-associate-dva-c02-practice-test-questions-and-exam-dumps-part9-q161-180\/","title":{"rendered":"Amazon AWS Certified Developer – Associate DVA-C02 Practice Test Questions and Exam Dumps Part9 Q161-180"},"content":{"rendered":"

View Full <\/b>Amazon AWS Certified Developer – Associate DVA-C02 Exam Dumps<\/b><\/a> and Practice Test Dumps.<\/b><\/h2>\n

 <\/p>\n

Question 161<\/b><\/h3>\n

A developer wants to ensure that an application can safely retry a request after a network timeout without creating duplicate records. Which technique should be implemented?<\/b><\/p>\n

    \n
  1. Compression<\/span><\/li>\n
  2. Idempotency<\/span><\/li>\n
  3. Caching<\/span><\/li>\n
  4. Sharding<\/span><\/li>\n<\/ol>\n

    Correct Answer: 2<\/b><\/p>\n

    Explanation<\/b><\/p>\n

    Idempotency allows an operation to produce the same intended result even when the same request is submitted multiple times. This is especially important in distributed systems because a network timeout does not always indicate that the original request failed. A client may retry the request, potentially causing duplicate records or transactions if the operation is not idempotent. Developers can use unique request or idempotency keys to identify repeated operations and return the existing result instead of performing the operation again. Compression reduces data size, caching stores reusable data, and sharding distributes data. Idempotency is therefore important for reliable retry behavior.<\/span><\/p>\n

    Question 162<\/b><\/h3>\n

    A developer needs to grant an EC2 application temporary access to an S3 bucket without storing access keys on the server. Which solution should be used?<\/b><\/p>\n

      \n
    1. IAM role attached to the EC2 instance<\/span><\/li>\n
    2. Root user credentials<\/span><\/li>\n
    3. Public S3 bucket<\/span><\/li>\n
    4. Hardcoded access keys<\/span><\/li>\n<\/ol>\n

      Correct Answer: 1<\/b><\/p>\n

      Explanation<\/b><\/p>\n

      An IAM role attached to an EC2 instance allows applications running on that instance to obtain temporary AWS credentials automatically. The AWS SDK can retrieve these credentials through the instance metadata service, eliminating the need to store long-term access keys on the server. The role should grant only the permissions required by the application. Using root credentials or hardcoded access keys creates unnecessary security risks, while making the S3 bucket public removes access control. IAM roles provide a secure and manageable approach for granting AWS permissions to applications running on EC2.<\/span><\/p>\n

      Question 163<\/b><\/h3>\n

      A developer wants to configure a Lambda function to process messages from an SQS queue in batches. Which feature should be used?<\/b><\/p>\n

        \n
      1. Lambda event source mapping<\/span><\/li>\n
      2. Lambda function URL<\/span><\/li>\n
      3. Lambda layer<\/span><\/li>\n
      4. Lambda alias<\/span><\/li>\n<\/ol>\n

        Correct Answer: 1<\/b><\/p>\n

        Explanation<\/b><\/p>\n

        Lambda event source mappings connect Lambda functions to supported event sources such as Amazon SQS. Lambda polls the queue and invokes the function with batches of messages according to the configured batch size and other event source settings. This removes the need for developers to implement continuous polling logic themselves. Function URLs expose Lambda through HTTP, layers package reusable dependencies, and aliases provide stable references to published versions. Event source mapping is therefore the appropriate feature when an application needs Lambda to automatically consume and process batches of SQS messages.<\/span><\/p>\n

        Question 164<\/b><\/h3>\n

        A developer wants to store application secrets and automatically rotate supported credentials. Which AWS service should be used?<\/b><\/p>\n

          \n
        1. Amazon S3<\/span><\/li>\n
        2. AWS Secrets Manager<\/span><\/li>\n
        3. Amazon CloudFront<\/span><\/li>\n
        4. Amazon ECR<\/span><\/li>\n<\/ol>\n

          Correct Answer: 2<\/b><\/p>\n

          Explanation<\/b><\/p>\n

          AWS Secrets Manager is designed to securely store sensitive information such as passwords, API keys, and database credentials. It also provides secret rotation capabilities for supported services and custom rotation workflows. Applications can retrieve secrets at runtime through the AWS SDK instead of embedding sensitive values in source code. S3 is an object storage service, CloudFront provides content delivery, and ECR stores container images. Secrets Manager is therefore appropriate when an application needs centralized secret storage combined with controlled access and credential rotation capabilities.<\/span><\/p>\n

          Question 165<\/b><\/h3>\n

          A developer wants to query a DynamoDB table using a partition key and a range of sort-key values. Which operation should be used?<\/b><\/p>\n

            \n
          1. Scan<\/span><\/li>\n
          2. Query<\/span><\/li>\n
          3. GetItem<\/span><\/li>\n
          4. DeleteItem<\/span><\/li>\n<\/ol>\n

            Correct Answer: 2<\/b><\/p>\n

            Explanation<\/b><\/p>\n

            The DynamoDB Query operation can retrieve items with a specified partition key and apply conditions to the sort key. For example, an application can query all records belonging to one customer where a timestamp falls within a specific range. Query is generally more efficient than Scan because DynamoDB can use the table or index key structure to locate the relevant items. GetItem retrieves a single item by its complete primary key, DeleteItem removes an item, and Scan examines items across a table or index. Query is therefore the correct operation for partition-key and sort-key access patterns.<\/span><\/p>\n

            Question 166<\/b><\/h3>\n

            A developer wants to send messages to a queue while ensuring that messages from the same group are processed in order. Which SQS queue type should be selected?<\/b><\/p>\n

              \n
            1. Standard<\/span><\/li>\n
            2. FIFO<\/span><\/li>\n
            3. Delay queue only<\/span><\/li>\n
            4. Dead-letter queue only<\/span><\/li>\n<\/ol>\n

              Correct Answer: 2<\/b><\/p>\n

              Explanation<\/b><\/p>\n

              Amazon SQS FIFO queues provide ordering capabilities for messages that belong to the same message group. The message group ID determines which messages must maintain their order. FIFO queues also provide deduplication capabilities that help prevent duplicate message processing within the supported FIFO behavior. Standard queues provide very high throughput but do not provide the same strict ordering guarantees. A delay queue controls when messages become visible, while a dead-letter queue handles messages that repeatedly fail processing. FIFO is therefore appropriate when message ordering is a required application characteristic.<\/span><\/p>\n

              Question 167<\/b><\/h3>\n

              A developer wants to monitor the number of errors produced by an application and notify an operations team when the value exceeds a threshold. Which combination should be used?<\/b><\/p>\n

                \n
              1. CloudWatch metric and CloudWatch alarm<\/span><\/li>\n
              2. S3 bucket and lifecycle rule<\/span><\/li>\n
              3. DynamoDB table and TTL<\/span><\/li>\n
              4. ECR repository and image tag<\/span><\/li>\n<\/ol>\n

                Correct Answer: 1<\/b><\/p>\n

                Explanation<\/b><\/p>\n

                CloudWatch metrics provide measurable application and AWS resource information, while CloudWatch alarms evaluate those metrics against configured thresholds. An alarm can trigger an action such as publishing a notification through Amazon SNS when the monitored metric enters a specified state. This combination is useful for monitoring application errors, latency, CPU utilization, throttling, and other operational indicators. S3 lifecycle rules manage object storage, DynamoDB TTL handles item expiration, and ECR manages container images. CloudWatch metrics combined with alarms therefore provide the monitoring and notification capabilities required by this scenario.<\/span><\/p>\n

                Question 168<\/b><\/h3>\n

                A developer wants to deploy infrastructure repeatedly using a version-controlled definition instead of configuring resources manually. Which service should be used?<\/b><\/p>\n

                  \n
                1. Amazon Route 53<\/span><\/li>\n
                2. AWS CloudFormation<\/span><\/li>\n
                3. Amazon SQS<\/span><\/li>\n
                4. Amazon Cognito<\/span><\/li>\n<\/ol>\n

                  Correct Answer: 2<\/b><\/p>\n

                  Explanation<\/b><\/p>\n

                  AWS CloudFormation enables developers to define AWS infrastructure using templates. The templates can be stored in version control and reused to create consistent environments. Resources such as Lambda functions, IAM roles, DynamoDB tables, S3 buckets, and API Gateway APIs can be defined together with their relationships and configuration. This infrastructure-as-code approach improves repeatability and reduces configuration drift. Route 53 provides DNS services, SQS provides messaging, and Cognito manages application identities. CloudFormation is therefore appropriate when infrastructure needs to be deployed consistently and managed through reusable, version-controlled definitions.<\/span><\/p>\n

                  Question 169<\/b><\/h3>\n

                  A developer needs to expose a Lambda function through an API that supports authorization, throttling, and managed API stages. Which service should be used?<\/b><\/p>\n

                    \n
                  1. Amazon S3<\/span><\/li>\n
                  2. Amazon API Gateway<\/span><\/li>\n
                  3. Amazon ElastiCache<\/span><\/li>\n
                  4. Amazon ECR<\/span><\/li>\n<\/ol>\n

                    Correct Answer: 2<\/b><\/p>\n

                    Explanation<\/b><\/p>\n

                    Amazon API Gateway provides managed APIs that can integrate with Lambda and other backend services. It supports capabilities such as authorization, throttling, stages, request and response handling, and monitoring integrations. API Gateway allows developers to expose application functionality through HTTP endpoints without operating their own API servers. S3 provides object storage, ElastiCache provides caching, and ECR stores container images. When an application requires a managed API layer with features such as authorization and throttling, API Gateway is an appropriate service for integrating clients with Lambda-backed functionality.<\/span><\/p>\n

                    Question 170<\/b><\/h3>\n

                    A developer wants to automatically trigger a Lambda function when an object is created in an S3 bucket. Which mechanism should be configured?<\/b><\/p>\n

                      \n
                    1. S3 event notification<\/span><\/li>\n
                    2. S3 Inventory<\/span><\/li>\n
                    3. S3 Lifecycle<\/span><\/li>\n
                    4. S3 Object Lock<\/span><\/li>\n<\/ol>\n

                      Correct Answer: 1<\/b><\/p>\n

                      Explanation<\/b><\/p>\n

                      S3 event notifications allow Amazon S3 to send notifications when supported object-level events occur, such as object creation. A Lambda function can be configured as a destination for the notification, enabling event-driven processing immediately after the object event. This pattern is useful for image processing, file validation, document transformation, and metadata extraction. S3 Inventory provides periodic object reports, Lifecycle manages object transitions and expiration, and Object Lock provides retention protection. S3 event notifications are therefore the appropriate mechanism for triggering Lambda based on object creation events.<\/span><\/p>\n

                      Question 171<\/b><\/h3>\n

                      A developer wants to reduce the latency of frequently accessed objects stored in S3 for users around the world. Which service should be used?<\/b><\/p>\n

                        \n
                      1. Amazon CloudFront<\/span><\/li>\n
                      2. Amazon RDS<\/span><\/li>\n
                      3. Amazon SQS<\/span><\/li>\n
                      4. Amazon ECR<\/span><\/li>\n<\/ol>\n

                        Correct Answer: 1<\/b><\/p>\n

                        Explanation<\/b><\/p>\n

                        Amazon CloudFront is a content delivery network that caches content at edge locations distributed geographically. When users request frequently accessed S3 objects, CloudFront can serve cached content from an edge location closer to the user instead of requiring every request to travel to the S3 origin. This can reduce latency and improve application performance. RDS provides relational databases, SQS provides message queues, and ECR stores container images. CloudFront is therefore appropriate for globally distributing static S3 content and improving response times for users in different geographic locations.<\/span><\/p>\n

                        Question 172<\/b><\/h3>\n

                        A developer needs to retrieve multiple known objects from S3 using an application without making the bucket public. Which approach should be considered?<\/b><\/p>\n

                          \n
                        1. Generate presigned URLs for the required objects.<\/span><\/li>\n
                        2. Make the bucket publicly readable.<\/span><\/li>\n
                        3. Disable Block Public Access.<\/span><\/li>\n
                        4. Use root credentials in the application.<\/span><\/li>\n<\/ol>\n

                          Correct Answer: 1<\/b><\/p>\n

                          Explanation<\/b><\/p>\n

                          Presigned URLs allow applications to provide temporary access to private S3 objects without making the bucket public. The application generates each URL using credentials that have permission to access the corresponding object. The URL can include an expiration period, after which it is no longer valid for the authorized operation. This approach is useful when clients need temporary access but should not receive AWS credentials. Public bucket access and disabling Block Public Access unnecessarily expose resources, while root credentials should never be embedded in applications. Presigned URLs provide controlled, temporary access to private objects.<\/span><\/p>\n

                          Question 173<\/b><\/h3>\n

                          A developer wants to store a value in DynamoDB only if an item with the same key does not already exist. Which feature should be used?<\/b><\/p>\n

                            \n
                          1. ConditionExpression<\/span><\/li>\n
                          2. ProjectionExpression<\/span><\/li>\n
                          3. FilterExpression<\/span><\/li>\n
                          4. Scan<\/span><\/li>\n<\/ol>\n

                            Correct Answer: 1<\/b><\/p>\n

                            Explanation<\/b><\/p>\n

                            A DynamoDB ConditionExpression can prevent a write operation from succeeding unless a specified condition is true. For example, an application can use an attribute-not-exists condition to ensure that a new item is created only when an item with the same key does not already exist. This is useful for preventing accidental overwrites and implementing application-level concurrency controls. ProjectionExpression controls returned attributes, FilterExpression filters retrieved results, and Scan examines items across a table or index. ConditionExpression is therefore the appropriate mechanism for enforcing a condition before writing an item.<\/span><\/p>\n

                            Question 174<\/b><\/h3>\n

                            A developer wants to route different application events to different Lambda functions based on event attributes. Which service should be used?<\/b><\/p>\n

                              \n
                            1. Amazon EventBridge<\/span><\/li>\n
                            2. Amazon ECR<\/span><\/li>\n
                            3. Amazon ElastiCache<\/span><\/li>\n
                            4. Amazon RDS<\/span><\/li>\n<\/ol>\n

                              Correct Answer: 1<\/b><\/p>\n

                              Explanation<\/b><\/p>\n

                              Amazon EventBridge provides event buses and rules that can evaluate event patterns and route matching events to configured targets. A developer can create different rules for different event types and send them to separate Lambda functions or other AWS services. This enables loosely coupled event-driven architectures where producers do not need direct knowledge of every consumer. ECR manages container images, ElastiCache provides in-memory caching, and RDS provides relational databases. EventBridge is therefore appropriate when routing decisions need to be based on event content and multiple application components need to respond independently.<\/span><\/p>\n

                              Question 175<\/b><\/h3>\n

                              A developer wants to execute a Lambda function whenever a message is published to an SNS topic. Which configuration should be used?<\/b><\/p>\n

                                \n
                              1. SNS topic subscription to the Lambda function<\/span><\/li>\n
                              2. S3 lifecycle rule<\/span><\/li>\n
                              3. DynamoDB TTL<\/span><\/li>\n
                              4. CloudFront origin<\/span><\/li>\n<\/ol>\n

                                Correct Answer: 1<\/b><\/p>\n

                                Explanation<\/b><\/p>\n

                                An SNS topic can have a Lambda function as a subscription endpoint. When a message is published to the topic, SNS delivers the message to the subscribed Lambda function for processing. This supports event-driven architectures in which publishers are separated from consumers. Multiple subscribers can also receive the same SNS message, enabling fanout patterns. S3 lifecycle rules manage object retention, DynamoDB TTL removes expired items, and CloudFront origins define content sources. An SNS subscription to Lambda is therefore appropriate when a Lambda function should automatically process messages published to an SNS topic.<\/span><\/p>\n

                                Question 176<\/b><\/h3>\n

                                A developer wants to process a large dataset in parallel using independent compute tasks. Which AWS architecture can provide scalable containerized processing?<\/b><\/p>\n

                                  \n
                                1. Amazon ECS with AWS Fargate<\/span><\/li>\n
                                2. Amazon Route 53<\/span><\/li>\n
                                3. Amazon S3 Inventory only<\/span><\/li>\n
                                4. AWS KMS<\/span><\/li>\n<\/ol>\n

                                  Correct Answer: 1<\/b><\/p>\n

                                  Explanation<\/b><\/p>\n

                                  Amazon ECS with AWS Fargate can run multiple container tasks without requiring developers to manage the underlying servers. A workload can be divided into independent tasks and scaled according to processing requirements. Fargate provides serverless compute for ECS containers, while ECS manages task definitions, services, and scheduling. Route 53 provides DNS services, S3 Inventory generates object reports, and KMS manages encryption keys. ECS with Fargate is therefore a suitable architecture for scalable containerized processing where independent tasks can execute concurrently and the development team does not want to manage EC2 instances.<\/span><\/p>\n

                                  Question 177<\/b><\/h3>\n

                                  A developer wants to automatically retry an AWS SDK request after receiving a transient throttling error. Which strategy should be used?<\/b><\/p>\n

                                    \n
                                  1. Exponential backoff with jitter<\/span><\/li>\n
                                  2. Immediate unlimited retries<\/span><\/li>\n
                                  3. Disable all retries<\/span><\/li>\n
                                  4. Retry continuously without delay<\/span><\/li>\n<\/ol>\n

                                    Correct Answer: 1<\/b><\/p>\n

                                    Explanation<\/b><\/p>\n

                                    Exponential backoff increases the waiting period between successive retry attempts, giving the affected AWS service time to recover from temporary throttling or other transient failures. Adding jitter introduces randomness into retry delays, helping prevent many clients from retrying simultaneously and creating another traffic spike. Immediate unlimited retries can increase service load and make throttling worse. Disabling all retries may cause applications to fail unnecessarily when the problem is temporary. AWS SDKs provide retry mechanisms, but developers should understand and configure retry behavior according to workload requirements. Exponential backoff with jitter is a common resilience technique.<\/span><\/p>\n

                                    Question 178<\/b><\/h3>\n

                                    A developer wants to allow an application to authenticate users and obtain AWS credentials for accessing AWS resources from a client application. Which service is relevant?<\/b><\/p>\n

                                      \n
                                    1. Amazon Cognito<\/span><\/li>\n
                                    2. Amazon ECR<\/span><\/li>\n
                                    3. Amazon CloudFront<\/span><\/li>\n
                                    4. Amazon ElastiCache<\/span><\/li>\n<\/ol>\n

                                      Correct Answer: 1<\/b><\/p>\n

                                      Explanation<\/b><\/p>\n

                                      Amazon Cognito provides capabilities for application authentication, authorization, and user identity management. User pools can manage application users and authentication, while identity pools can provide temporary AWS credentials for authorized users when configured for that purpose. This is useful for applications such as mobile and web applications that need user authentication and controlled access to AWS resources. ECR stores container images, CloudFront provides content delivery, and ElastiCache provides caching. Cognito is therefore relevant when an application needs managed user identity capabilities and, where appropriate, temporary AWS access for authenticated clients.<\/span><\/p>\n

                                      Question 179<\/b><\/h3>\n

                                      A developer wants to collect application events from multiple AWS services and route them to a centralized event bus. Which service provides this capability?<\/b><\/p>\n

                                        \n
                                      1. Amazon EventBridge<\/span><\/li>\n
                                      2. Amazon ECR<\/span><\/li>\n
                                      3. Amazon RDS<\/span><\/li>\n
                                      4. Amazon ElastiCache<\/span><\/li>\n<\/ol>\n

                                        Correct Answer: 1<\/b><\/p>\n

                                        Explanation<\/b><\/p>\n

                                        Amazon EventBridge provides event buses that can receive events from AWS services, applications, and supported external sources. Rules can then evaluate the events and route matching events to targets such as Lambda, SQS, SNS, or Step Functions. This creates a centralized event-routing layer and reduces direct dependencies between producers and consumers. ECR stores container images, RDS provides relational databases, and ElastiCache provides in-memory caching. EventBridge is therefore suitable for architectures that need to collect, filter, and route events from multiple sources using event-driven rules.<\/span><\/p>\n

                                        Question 180<\/b><\/h3>\n

                                        A developer wants to ensure that a message that fails repeatedly does not remain in the main SQS queue indefinitely. Which feature should be configured?<\/b><\/p>\n

                                          \n
                                        1. Dead-letter queue<\/span><\/li>\n
                                        2. Long polling<\/span><\/li>\n
                                        3. Message delay<\/span><\/li>\n
                                        4. Queue encryption only<\/span><\/li>\n<\/ol>\n

                                          Correct Answer: 1<\/b><\/p>\n

                                          Explanation<\/b><\/p>\n

                                          An SQS dead-letter queue can receive messages that have failed processing after a configured number of delivery attempts. The source queue uses a redrive policy to specify the maximum receive count before the message is moved to the dead-letter queue. This prevents problematic messages from repeatedly consuming processing resources and allows developers to inspect failed messages separately. Long polling reduces empty receive requests, message delay controls when messages become available, and encryption protects message contents. A dead-letter queue is therefore the appropriate feature for isolating messages that repeatedly fail processing.<\/span><\/p>\n

                                           <\/p>\n","protected":false},"excerpt":{"rendered":"

                                          View Full Amazon AWS Certified Developer – Associate DVA-C02 Exam Dumps and Practice Test Dumps.   Question 161 A developer wants to ensure that an application can safely retry a request after a network timeout without creating duplicate records. Which technique should be implemented? Compression Idempotency Caching Sharding Correct Answer: 2 Explanation Idempotency allows an […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":[],"categories":[1648,1647],"tags":[],"_links":{"self":[{"href":"https:\/\/www.examlabs.com\/certification\/wp-json\/wp\/v2\/posts\/18790"}],"collection":[{"href":"https:\/\/www.examlabs.com\/certification\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.examlabs.com\/certification\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.examlabs.com\/certification\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.examlabs.com\/certification\/wp-json\/wp\/v2\/comments?post=18790"}],"version-history":[{"count":1,"href":"https:\/\/www.examlabs.com\/certification\/wp-json\/wp\/v2\/posts\/18790\/revisions"}],"predecessor-version":[{"id":18791,"href":"https:\/\/www.examlabs.com\/certification\/wp-json\/wp\/v2\/posts\/18790\/revisions\/18791"}],"wp:attachment":[{"href":"https:\/\/www.examlabs.com\/certification\/wp-json\/wp\/v2\/media?parent=18790"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.examlabs.com\/certification\/wp-json\/wp\/v2\/categories?post=18790"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.examlabs.com\/certification\/wp-json\/wp\/v2\/tags?post=18790"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}