A company is migrating backup storage to AWS and needs a cloud-backed storage solution that keeps a local cache for on-premises access. Which AWS service provides this capability?

AWS Storage Gateway is the correct choice because it provides hybrid cloud storage with local caching. It acts as a bridge between on-premises environments and AWS cloud storage, allowing companies to store data in the cloud while maintaining a local cache for low-latency access to frequently used data. This is ideal for backup storage migration where on-premises access is still required. AWS Snowcone is an edge computing and data transfer device, not a hybrid storage solution with caching. AWS Backup is a centralized backup service but doesn't provide a local cache for on-premises access. Amazon EFS is a scalable, elastic file storage for EC2 instances and on-premises access via Direct Connect or VPN, but it's not primarily designed as a cached gateway for migrating existing on-premises backup storage to the cloud.