In computer security, what is a virus?

A virus is defined as a type of malware that replicates and spreads by inserting copies of itself into other programs, files, or the boot sector of a computer’s hard drive. When the infected program is executed, the virus activates and can disrupt system operations, corrupt data, or even compromise security. This self-replicating nature allows viruses to spread to other systems, often without the user’s knowledge, making them a significant threat in the realm of computer security.

The other options do not accurately describe what a virus is. For instance, the first choice refers to anti-virus software, which is designed to detect and remove malware, not function as the malware itself. The second option inaccurately categorizes a virus as hardware, while viruses are strictly software programs. The fourth option describes a utility function, which is focused on file cleanup rather than the propagation of malicious software. Therefore, the correct identification of a virus as a type of malware that replicates and spreads is crucial for understanding how to defend against and mitigate its impact on computer systems.