Which of the following statements regarding personal operating systems is NOT true?

A. All operating systems for desktop and laptop computers also work on mobile devices such as tablets and smart phones.

B. New versions of operating system are released on a regular basis to keep up with developments in hardware and software.

C. There are a number of different personal operating systems, each with their own strengths and weaknesses.

D. Despite their differences, personal operating systems have a lot in common in terms of functionality. ​