An ecommerce application in a single Region uses a five-node Amazon Aurora MySQL cluster that handles many writes. The company must replicate the Aurora data to another Region for disaster recovery with an RPO of 1 hour and at lowest possible cost. Which solution provides the required replication at the lowest cost?

The correct solution is to use AWS DMS with a CDC task to replicate ongoing changes to an Amazon S3 bucket in another Region. This meets the RPO of 1 hour by continuously capturing changes and offers the lowest cost as S3 storage is inexpensive, and DMS provides efficient data transfer. Converting to an Aurora global database provides a much lower RPO (seconds) but is significantly more expensive than the requirement. Enabling Aurora Backtrack is for point-in-time recovery within the same Region, not cross-Region disaster recovery. Disabling automated Aurora backups and manually configuring hourly backups to another Region would be complex, less reliable, and potentially more expensive due to custom scripting and management overhead compared to DMS.