Final answer:
Malware is a category of harmful software that includes viruses, worms, Trojan horses, spyware, and adware; it's designed to infiltrate and damage computers without consent.
Step-by-step explanation:
The correct answer to the question is A) Malware. The term malware is an abbreviation for malicious software and refers to a broad category of harmful software designed to infiltrate, damage, or disable computers and computer systems without the user's consent. Malware includes various types of software threats like viruses, worms, Trojan horses, spyware, and adware. A virus is a type of malware that attaches itself to a legitimate program and can replicate, while a worm is a standalone malware that replicates itself to spread to other computers. A Trojan horse masquerades as a legitimate program but when executed, can deliver a malicious payload. Spyware is designed to spy on user actions to collect personal information without consent, and adware is software that shows unwanted advertisements.