Final answer:
A support agent would find System Restore the least useful for managing files and folders, while Disk Cleanup, File Explorer, and Disk Partition Manager are more directly related to file and folder management tasks.
Step-by-step explanation:
Among the utility tools listed, a support agent would least likely find System Restore useful for solving problems with file and folder management. This is because System Restore is primarily designed to restore system files, programs, and registry settings to a previous state, as a way to fix system errors and other issues after installing new software or drivers, rather than to directly manage files and folders.
On the other hand, Disk Cleanup is useful for removing temporary files and freeing up space. File Explorer is essential for browsing, opening, moving, and organizing files and folders. Lastly, a Disk Partition Manager is used for creating, deleting, resizing, and managing partitions on a hard drive, which also indirectly affects file system management.