AWS Certified Developer – Associate (DVA-C02) — Question 120

A company needs to develop a proof of concept for a web service application. The application will show the weather forecast for one of the company's office locations. The application will provide a REST endpoint that clients can call. Where possible, the application should use caching features provided by AWS to limit the number of requests to the backend service. The application backend will receive a small amount of traffic only during testing.

Which approach should the developer take to provide the REST endpoint MOST cost-effectively?

Answer options

• A. Create a container image. Deploy the container image by using Amazon Elastic Kubernetes Service (Amazon EKS). Expose the functionality by using Amazon API Gateway.
• B. Create an AWS Lambda function by using the AWS Serverless Application Model (AWS SAM). Expose the Lambda functionality by using Amazon API Gateway.
• C. Create a container image. Deploy the container image by using Amazon Elastic Container Service (Amazon ECS). Expose the functionality by using Amazon API Gateway.
• D. Create a microservices application. Deploy the application to AWS Elastic Beanstalk. Expose the AWS Lambda functionality by using an Application Load Balancer.

Correct answer: B

Explanation

Option B is the most cost-effective choice because AWS Lambda operates on a pay-per-use model, making it ideal for low-traffic applications, especially during testing. Other options like Amazon EKS and ECS involve higher operational overhead and costs due to the need for managing containers and infrastructure, which is unnecessary for a simple proof of concept.