Software that acts without a user's knowledge and deliberately alters the computer's operations is called _____.

A) malware
B) a virus
C) a worm
D) spyware

Malware (short for malicious software) is a general term used to describe any program or code that is designed to harm a computer system or data, or to otherwise perform actions without the user's knowledge or consent. Virus, worm, and spyware are all examples of malware, but malware encompasses a broader range of malicious software.