AWS Certified Cloud Practitioner Practice Test 3

Amazon ElastiCache provides in-memory caching which improves performance for read requests when the data is cached in ElastiCache. ElastiCache can be placed in front of your database.

Amazon RDS is a relational SQL type of database. It is not a service that you place in front of another database to improve performance. Instead you might use RDS as your back-end database and use ElastiCache in front of it to improve performance through its in-memory caching.

Amazon EFS is an Elastic File System, not a caching service.

Amazon RedShift is a data warehouse that is used for performing analytics on data.

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