Answer:A malicious software disguised as a legitimate program is called a Trojan Horse or simply a Trojan.--- Trojan Horse (Trojan)Definition: A type of malware that pretends to be a harmless or useful program to trick users into installing it.How it works: Once installed, it can:Steal data (passwords, personal info)Open a backdoor for hackersDamage or delete filesSpy on user activityName origin: Inspired by the Greek myth of the Trojan Horse, where Greek soldiers hid inside a wooden horse to infiltrate the city of Troy.--- Example:A fake email attachment claiming to be a "security update" that installs malware when opened.Let me know if you want help identifying or protecting against Trojans.