Correct answer - "Cognito User Pools" : A user pool is a user directory in Amazon Cognito. With a
user pool, your users can sign in to your web or mobile app through Amazon Cognito. Your users
can also sign in through social identity providers like Facebook or Amazon, and through SAML
identity providers
"IAM permissions with sigv4" - We cannot possibly create an IAM user for every visitor of the
site, so this is where social identity providers come in to help"Lambda Authorizer" - This is a
good option as well that helps access to API Gateway but Cognito is a better option in that it
handles alot for you that you don't need to implement
"Lambda Authorizer" - This won't be a fully managed user management solution but it would allow
you to check for access at the AWS API Gateway level