A. Configure AWS Backup to perform cross-Region backups of all servers every 5 minutes. Reprovision the three tiers in the DR Region from the backups using AWS CloudFormation in the event of a disaster.
B. Maintain another running copy of the web and application server stack in the DR Region using AWS CloudFormation drift detection. Configure cross-Region snapshots of the DB instance to the DR Region every 5 minutes. In the event of a disaster, restore the DB instance using the snapshot in the DR Region.
C. Use Amazon EC2 Image Builder to create and copy AMIs of the web and application server to both the primary and DR Regions. Create a cross-Region read replica of the DB instance in the DR Region. In the event of a disaster, promote the read replica to become the master and reprovision the servers with AWS CloudFormation using the AMIs.
D. Create AMIs of the web and application servers in the DR Region. Use scheduled AWS Glue jobs to synchronize the DB instance with another DB instance in the DR Region. In the event of a disaster, switch to the DB instance in the DR Region and reprovision the servers with AWS CloudFormation using the AMIs.