Which of the following is an example of Single User operating system?

1. Windows 7
2. Windows 8
3. Windows 3.1
4. Windows Vista

iOS is a mobile operating system developed by …………… company.

1. Microsoft
2. Apple
3. Nokia
4. Google

Which was the first commercially available phone to run Android?

1. Nokia Lumia
2. iPhone5
3. HTC Dream
4. Samsung Galaxy

…………… is loaded first and remains in the memory until the operating system is shut down.

1. Shell
2. kernel
3. Application
4. None of these