A company wants to build a web application on AWS. Client access requests to the website are not predictable and can be idle for a long time. Only customers who have paid a subscription fee can have the ability to sign in and use the web application. Which combination of steps will meet these requirements MOST cost-effectively? (Choose three.)

The correct options provide a serverless, scalable, and cost-effective solution. Amazon Cognito user pools are ideal for managing user authentication for subscription-based access. AWS Lambda and Amazon API Gateway create a serverless backend that scales automatically and incurs costs only when requests are processed, making it cost-effective for unpredictable traffic. Storing user information in Amazon DynamoDB, a NoSQL database, offers high performance and scalability. AWS Amplify, integrated with Amazon CloudFront, efficiently delivers static frontend content (HTML, CSS, JS) globally with low latency. Incorrect options: Amazon ECS behind an Application Load Balancer is less cost-effective for idle applications than serverless Lambda, as ECS instances would incur costs even when idle. Amazon Cognito identity pools are primarily for authorizing access to AWS resources, not for authenticating users into an application. Amazon