An ecommerce company wants a disaster recovery solution for its Amazon RDS DB instances that run Microsoft SQL Server Enterprise Edition. The company's current recovery point objective (RPO) and recovery time objective (RTO) are 24 hours. Which solution will meet these requirements MOST cost-effectively?

Copying automatic snapshots to another Region every 24 hours is the most cost-effective solution that meets the RPO and RTO of 24 hours. RDS automatic snapshots are taken daily, and copying them cross-Region provides a disaster recovery strategy. If a disaster occurs, a new DB instance can be restored from the copied snapshot in the target Region. This approach is cost-effective because you only pay for storage of the snapshots and data transfer, rather than maintaining a continuously running replica. Creating a cross-Region read replica offers a much lower RPO/RTO (typically seconds to minutes) but is significantly more expensive as it involves running a full replica instance continuously. AWS DMS is a migration service, not primarily designed for continuous disaster recovery replication for RDS, and would be more complex and costly to set up for this specific use case. Using cross-Region replication for native backups to S3 every 24 hours is less integrated with RDS's native DR capabilities and could be more complex to manage and restore from compared to RDS snapshots.