Correct answer - "DynamoDB" : DynamoDB Streams captures a time-ordered sequence of item-level
modifications in any DynamoDB table, and stores this information in a log for up to 24 hours.
Applications can access this log and view the data items as they appeared before and after they
were modified, in near real time.
"RDS" - A relational database works different than a NoSQL database such as DynamoDB. However you
can use Amazon Kinesis for streaming with Relational data
"ElastiCache" - ElastiCache works as an in-memory data store and cache
"Kinesis" - Kinesis streams is similar to DynamoDB streams although different but with Kinesis
you use it for processing larges amounts of data whereas DynamoDB streams is for the service
itself