The correct answer is: D. All
An operating system (OS) is system software that manages computer hardware and software resources and provides common services for computer programs. Operating systems are found on many devices that contain a computerâfrom cellular phones and personal computers to supercomputers and Web servers.
Application software (app software) is a type of computer program that performs a specific task or set of tasks for an end-user (client). Examples of application software include word processors, spreadsheets, database management systems, web browsers, and media players.
System software is a type of computer program that is designed to run a computer’s hardware and application programs. System software includes the operating system, device drivers, and other programs that control the computer’s hardware and provide a platform for application programs to run on.
All of these types of software run on computer hardware and serve as a platform for other software to run on.