"When an interrupt or a system call transfers control to the operating system, a kernel stack area separate from the stack of the interrupted process is generally used. Why?"

Explanation:

There are two reasons, first, the operating system could be blocked because a program with poorly written user program does not allow for enough stack space.

Second, the kernel can leave data in the user memory of a program, and this data can be used for another user to get another delicate information.

universal windows platform is an open source api created by microsoft and first introduced in windows 10. the purpose of this platform is to develop universal apps that run on windows 10, windows 10 mobile, xbox one and hololens without the need to be re-written for each. it supports windows app development using c++, c#, vb.net, and xaml. the api is implemented in c++, and supported in c++, vb.net, c#, f# and javascript. designed as an extension to the windows runtime platform first introduced in windows server 2012 and windows 8, uwp allows developers to create apps that will potentially run on multiple types of devices.

answer; i believe the correct answer is (b) by using a multimeter;