Which keys can be pressed quit without saving in DOS

Answer: Option C

In Disk Operating System (DOS), the key combination that can be pressed to quit without saving is Ctrl + C. This key combination sends a termination signal to the running program or command, allowing you to exit without saving changes or stopping the current operation.

Option A, "Ctrl + A," does not typically have a special meaning in DOS and is not used for quitting without saving.
Option B, "Ctrl + B," and Option D, "Ctrl + D," also do not have specific meanings for quitting without saving in DOS.

Therefore, the correct answer is Option C: Ctrl + C.