The correct answer is C because it addresses all the organization's requirements: ensuring data durability and availability through ZRS and GRS, complying with data protection regulations by storing backups in a separate region, and optimizing for cost-effectiveness with a combination of full and incremental backups. Option A fails to provide a comprehensive backup strategy, Option B does not ensure data availability in case of a regional outage, and Option D is not a reliable disaster recovery strategy as it lacks data replication and backups.