Correct answer - "RDS Read Replicas" : You can reduce the load on your source DB instance by
routing read queries from your applications to the read replica. In other words for read-only
queries, change the database source in the application to point to the new read replica
database.
Incorrect:
"RDS Multi AZ" - In a Multi-AZ deployment, Amazon RDS automatically provisions and maintains a
synchronous standby replica in a different Availability Zone in which no changes are made on
your part
"RDS backups" - You can create a backup manually or automated it but no change to the code is
required
"RDS Maintenance Upgrades" - Some maintenance items require that Amazon RDS take your DB instance
offline for a short time which does not involve code changes