Which type of malware is designed to take control of a user's system by disguising itself as legitimate software?

The type of malware that is designed to take control of a user's system by disguising itself as legitimate software is known as a Trojan horse. This form of malware operates by tricking users into executing it, often by presenting itself as a useful application or file. Once the user runs the Trojan, it can perform various malicious activities, ranging from stealing personal information to providing unauthorized access to attackers.

Trojan horses differ from other types of malware because they do not replicate themselves like viruses or worms; instead, they rely on social engineering tactics to convince users to install them willingly. This deception is critical to their functionality, as the success of a Trojan relies heavily on its ability to appear harmless or beneficial to the user.

The other options represent different forms of malware with distinct characteristics. Ransomware typically encrypts a user's files and demands payment for the decryption key. A virus attaches itself to clean files and spreads to other files, often corrupting or altering them in the process. Worms are self-replicating programs that spread over networks and can operate independently without human intervention. Each of these forms of malware functions differently and has unique methods of infection and propagation, but it is the Trojan horse that specifically disguises itself as legitimate software to gain control of