Concept:Ctrl + Alt + Del is a standard keyboard command used to access system options, including restart or reboot.
Explanation:The shortcut Ctrl + Alt + Del is commonly called the "three-finger salute."
On Windows operating systems, pressing this key combination brings up the security screen or Task Manager.
From that screen, the user can select Restart, Shut Down, Lock, or Sign Out.
This makes it the correct command for rebooting the computer among the given options.
The other listed combinations, Ctrl + Del, Ctrl + Alt + C, and Ctrl + Alt, do not perform the reboot function.
Answer:A. Ctrl + Alt + Del