What is application software?

A. Application software is used to fill in applications on the Internet.

B. Application software is the same as the operating system of a computer.

C. Application software connects the printer to the computer.

D. Application software are programs installed on a computer's operating system.

I believe it's (D) because, An application is any program, or group of programs, that is designed for the end user. Application software can be divided into two general classes: systems software and applications software. Applications software (also called end-user programs) include such things as database programs, word processors, Web browsers and spreadsheets.