answer from chatgpt
The most operationally efficient solution that meets the requirements would be option C.
This solution involves deploying the application as AWS Lambda functions and setting up Amazon API Gateway REST API endpoints for the application. Additionally, setting up an Amazon Cognito user pool and configuring an Amazon Cognito authorizer to handle user authentication.
This approach provides the desired level of abstraction as the application team would not have to maintain any infrastructure or servers. Also, AWS Lambda functions are a highly scalable and cost-effective way to build serverless applications. And by using the Amazon Cognito, it will handle all the user authentication and access management which is highly secure and manageable.