You are currently deploying an application that needs to have a sign-up and sign-in functionality added. As much as possible, you would want to reduce the coding effort required for these modules. You also need to ensure that code is executed automatically after the sign-in process is complete. How can you achieve this? Choose 3 answers from the options below.

Answer options:

A.Use the AWS Cognito service to provide the sign-up and sign-in functionality.
B.Use the AWS IAM service to provide the sign-up and sign-in functionality.
C.Use AWS Cloudwatch events to trigger code that will be run after the user sign-in process is complete.
D.Trigger a lambda function to execute the code associated with the post authentication event.

Answer – A, C and D
This is mentioned in the AWS Documentation.
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You can create an AWS Lambda function and then trigger that function during user pool operations such as user sign-up, confirmation, and sign-in (authentication) with a Lambda trigger. You can add authentication challenges, migrate users, and customize verification messages.
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Option B is incorrect since IAM cannot simulate the sign-in and sign-up process that the application would require.
For more information on using Lambda triggers with AWS Cognito, please refer to the below URL-
https://docs.aws.amazon.com/cognito/latest/developerguide/cognito-user-identity-pools-working-with-aws-lambda-triggers.html