The best way to remove unnecessary programs from a computer system using the operating system's features is through 'Application management.' This feature typically provides a user interface that allows users to view, manage, and uninstall applications installed on the system. Using this feature, you can select the programs that are not needed and choose to uninstall them, thereby freeing up system resources and storage space.
Reference: This is in line with the functions of application management features found in common operating systems like Windows and macOS, which are included in the CompTIA IT Fundamentals curriculum for understanding software management.