Disk Cleanup is the correct answer.

Disk Cleanup is a utility tool found in the Windows operating system that helps users free up disk space on their hard drive by identifying and removing unnecessary files. It is a built-in system tool that can be accessed through the Windows Start menu or by searching for "Disk Cleanup" in the search bar.

The main purpose of Disk Cleanup is to identify non-essential files on the hard disk and allow the user to choose whether or not to delete them. It scans various areas of the hard drive, including temporary files, system files, recycle bin, and other locations where unnecessary files may accumulate over time.

Here's how Disk Cleanup works and why it is the correct answer to the given question:

1. Identify non-essential files: Disk Cleanup analyzes the hard drive and identifies files that are not necessary for the proper functioning of the operating system or user applications. These files may include temporary internet files, system error memory dump files, old Windows installation files, and more.

2. User control over file deletion: Disk Cleanup does not automatically delete the identified files. Instead, it presents the user with a list of files to be deleted and allows them to select which files they want to remove. This ensures that essential files are not accidentally deleted.

3. Disk space reclamation: By removing unnecessary files, Disk Cleanup helps users free up disk space on their hard drive. This can be particularly useful for users who have limited storage capacity or want to optimize the performance of their computer.

4. Other features: In addition to removing files, Disk Cleanup also provides options to compress old files, which can save even more disk space by reducing the file size. It also allows users to remove unused Windows components and programs, further optimizing the system's performance.

In conclusion, Disk Cleanup is a utility tool that helps users identify non-essential files on their hard drive and allows them to choose whether or not to delete them. It is a useful tool for freeing up disk space and optimizing system performance.

Disk Cleanup utility identifies non-essential files and allows the user to delete them to free up disk space.