Which software is used to protect a computer from viruses?

Correct answer: Antivirus

The governing concept is the role of utility and security software in protecting a computer system. Antivirus software scans files, programs and sometimes network activity to detect, quarantine, block or remove malicious software such as viruses. It may also provide real-time protection against suspicious activity, although its effectiveness depends on updates and correct configuration. Therefore, Antivirus is the correct answer. A monitor is output hardware that displays information, a keyboard is input hardware used to enter data, and a hard disk is a storage device that holds files and programs. Those devices may be part of the computer system, but none is security software designed to detect viruses.