These are the type of programs, we generally download onto our computer system, disguised as useful and free software, but take control of our computer systems to damage our data.

Correct option is D

The correct answer is (d) Trojan
Explanation:
● A Trojan (or Trojan Horse) is a type of malware that disguises itself as legitimate or useful software (often free).
● Users are tricked into loading and executing the Trojan on their systems.
● Once installed, it can take control of the computer system, damage data, steal information, or open a backdoor for other malware.
Information Booster:
● Virus: A program that replicates itself by modifying other computer programs and inserting its own code.
● Worm: A standalone malware that replicates itself to spread to other computers, often over a network.
● Spam: Unsolicited messages sent in bulk, usually via email.
Additional Knowledge:
● The term comes from the Ancient Greek story of the deceptive wooden horse that led to the fall of the city of Troy.