Practice Test

1. A, C. First, a larger instance with the fastest possible volume type—provisioned IOPS—is generally going to improve overall performance, so A is a good idea. Second, ElastiCache will provide faster responses and reduce database reads over time. A and C are both valid approaches. A Multi-AZ setup is for disaster recovery, and sharding is high overhead and could potentially increase response time, rather than reduce it, in this use case.
2. B. redis and memcached are engines available for use by ElastiCache. reddit is an online information site, and Redshift is a data warehousing and OLAP service.
3. B, C. AWS allows a number of options for encrypting data at rest. In the supplied solutions, AWS Key Management Service (KMS) is an AWS-managed solution for data encryption, and customer-provided keys are allowed as well. In the latter case, customers provide the keys and AWS handles encryption of data using those keys. ElastiCache for memcached does not support encryption...