Correct answer - "DynamoDB" : Access to Amazon DynamoDB requires credentials. Those credentials
must have permissions to access AWS resources, such as an Amazon DynamoDB table. You can use AWS
Identity and Access Management (IAM) to help secure access to your DynamoDB service.
Incorrect:
"RDS MySQL" - With RDS you will can still use authentication and authorization however DynamoDB
is more flexible in that you can restrict actions on the table such as "dynamodb:Query",
"dynamodb:Scan"
"ElastiCache" - This service security settings are handled at the network level such as VPC or
security group
"MongoDB" - This database is not supported in RDS as of 2019 but can be used within AWS and you
can manually control authentication and authorization by allowing certain IP's or ports to be
accessed to a web server reading database queries