Answer:
Virus is the correct answer of this question.
Explanation:
A virus is a form of malicious that integrates its virus software to multiply by alteration applications and programs.By replicating malicious code the machine gets infected.It can self-, inject itself into other programs or files, and then infect them.
A virus is an adware program that is loaded without user knowledge into a user's device and performs malicious acts.virus damaged the computer system.