Which solution meets these requirements?
Create an Amazon RDS DB instance with synchronous replication to three nodes in three Availability Zones.
Create an Amazon RDS MySQL DB instance with Multi-AZ functionality enabled to synchronously replicate the data.
Create an Amazon RDS MySQL DB instance and then create a read replica in a separate AWS Region that synchronously replicates the data.
Create an Amazon EC2 instance with a MySQL engine installed that triggers an AWS Lambda function to synchronously replicate the data to an Amazon RDS MySQL DB instance.
Explanations:
While creating an Amazon RDS DB instance with synchronous replication to three nodes may seem like a good option, Amazon RDS does not support user-managed synchronous replication across multiple nodes; it only supports Multi-AZ deployments which handle failover automatically.
Creating an Amazon RDS MySQL DB instance with Multi-AZ functionality enabled ensures synchronous replication of data to a standby instance in a different Availability Zone, minimizing data loss and increasing reliability.
Creating a read replica in a separate AWS Region does not provide synchronous replication; read replicas are typically asynchronous, which means there is potential for data loss during a failover scenario.
Using an EC2 instance with a MySQL engine and AWS Lambda for replication is not a managed solution and introduces complexity and potential failure points. It does not guarantee synchronous replication and reliability required
I surmise that the answer is:
Create an Amazon RDS MySQL DB instance with Multi-AZ functionality enabled to synchronously replicate the data.