Answer: Enable binlog replication on the RDS primary node., Enable automatic backups on the source instance by setting the backup retention period to a value other than 0.

## Explanation When creating a read replica for Amazon RDS MySQL, there are specific prerequisites that must be met: **A. Enable binlog replication on the RDS primary node.** - **CORRECT** - For MySQL read replicas, binary logging must be enabled on the source DB instance - This is required because read replicas use MySQL's native binary log replication - Without binary logging enabled, replication cannot occur **E. Enable automatic backups on the source instance by setting the backup retention period to a value other than 0.** - **CORRECT** - Automatic backups must be enabled on the source DB instance - The backup retention period must be greater than 0 (typically at least 1 day) - This is a prerequisite for creating read replicas in RDS **Why the other options are incorrect:** **B. Choose a failover priority for the source DB instance.** - Incorrect - Failover priority is related to Multi-AZ deployments, not read replica creation - Read replicas don't require failover priority settings **C. Allow long-running transactions to complete on the source DB instance.** - Incorrect - While it's good practice to avoid creating replicas during heavy transactions, it's not a strict prerequisite - RDS can handle replication even with ongoing transactions **D. Create a global table and specify the AWS Regions where the table will be available.** - Incorrect - This refers to DynamoDB global tables, not RDS MySQL read replicas - Global tables are for DynamoDB, not RDS **Key AWS RDS Read Replica Prerequisites:** 1. Source DB instance must have automatic backups enabled (retention period > 0) 2. Binary logging must be enabled for MySQL/PostgreSQL engines 3. Source and replica must be in the same AWS Region (unless using cross-region replication) 4. Sufficient storage and I/O capacity on both instances

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