The requirements demand very low data loss (RPO < 1 minute) and fast recovery (RTO < 10 minutes) across Regions . Snapshot/backup-based approaches (B, D) generally cannot meet an RPO under 1 minute (and restoring snapshots/backups typically pushes RTO higher than 10 minutes for many real-world DB sizes and restore times).

Option A is the only choice that is explicitly built around near-real-time replication to another Region (cross-Region replica) and an operational pattern to promote the standby and update Route 53 to redirect applications quickly during failover.

Multi-AZ addresses in-Region high availability , while the cross-Region replica + promotion addresses cross-Region DR with low RPO and acceptable RTO when automated.

Why the others don’t meet the stated RPO/RTO:

B : Copying snapshots every 5 minutes immediately violates RPO < 1 minute .

C : DMS replication could potentially be low-latency, but the option only mentions notifications (no automated failover/redirect) and does not provide the clearest/most direct managed HA+DR pattern for the required RTO < 10 minutes .

D : “Cross-Region backups every 30 seconds ” is not a standard practical backup cadence for AWS Backup with RDS, and restore-based DR still tends to miss the RTO/RPO targets compared with replica promotion.