Exam AWS Certified Solutions Architect - Associate SAA-C03 topic 1 question 633 discussion

A Multi-AZ DB instance Creates a primary DB instance with one standby DB instance in a different Availability Zone. Using a Multi-AZ DB instance provides high availability, but the standby DB instance doesn't support connections for read workloads. Therefore you will need to create a read replica from the source DB instance then serve read traffic from the read replica.

Read replica split for read traffic will distribute the overall load and improve the performance. A: Standby replica cannot serve traffic (Correct me if I am wrong here) B: Transfer Accelerator is to speed up S3 traffic. Not the case here D: Kiensis will increase concurrency but won't solve the DB performance issues

you can’t read from the standby DB instance. If applications require more read capacity, you should create or add additional read replicas.

After you create a read replica from a source DB instance, the source becomes the primary DB instance. When you make updates to the primary DB instance, Amazon RDS copies them asynchronously to the read replica. https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/USER_ReadRepl.html