Which service should a solutions architect recommend to allow the application to copy files to AWS?

Explanations:

Amazon Elastic File System (Amazon EFS) provides scalable file storage for AWS cloud environments but does not provide a low-latency connection to on-premises servers or allow for seamless copying of files to AWS from an SMB file share without modifying the application.

Amazon FSx for Windows File Server is a fully managed Windows file system that supports SMB but is designed for a cloud environment. It requires modifying the application or network setup to directly interact with AWS, which is not feasible here due to the lack of application code changes.

AWS Snowball is a physical data transport solution designed for transferring large amounts of data into AWS. It is not suitable for ongoing, continuous file transfers like the ones described, especially with the need for low-latency connections.

AWS Storage Gateway enables seamless integration between on-premises environments and AWS storage services. Specifically, the File Gateway configuration allows SMB file shares to copy files directly to AWS, providing the necessary low-latency connection while minimizing changes to the application.