Which Amazon S3 feature uses the AWS backbone network and edge locations to reduce latency between end users and S3?

S3 Transfer Acceleration uses Amazon CloudFront's globally distributed edge locations and the AWS backbone network to speed up data transfers to and from S3 buckets. This reduces latency for users worldwide by routing data through the nearest edge location, which then uses optimized network paths to S3. S3 Cross-Region Replication is for automatically copying objects between buckets in different AWS Regions, not for accelerating end-user uploads/downloads. S3 Event Notifications alert you to changes in your S3 bucket. S3 Standard-Infrequent Access (S3 Standard-IA) is a storage class for data that is accessed less frequently but requires rapid access when needed, not a feature for transfer acceleration.