The AES cipher begins and ends with a(n) _________ stage because any other stage, applied at the beginning or end, is reversible without knowledge of the key and would add no security.

In the file name, Resume.docx, docx is the ________, indicating the file type

Fill in the blank(s) with correct word

Requested resources are granted to processes whenever possible with _________ .

A) ?preemption ? B) ?deadlock detection C) ?mutual exclusion ? D) ?deadlock avoidance