Which type of software is used to detect viruses on a computer?

The correct choice is anti-virus software, which is specifically designed to detect, prevent, and remove malicious software, commonly known as viruses, from a computer. This type of software works by scanning files and programs on the system, comparing them against a database of known malware signatures. If it identifies a matching signature, it can either quarantine or delete the potentially harmful file to protect the computer from infection.

In addition to detecting viruses, anti-virus solutions often include features to combat various other types of malware, such as worms and Trojans. Users typically schedule regular scans and receive updates to the software to ensure they have the latest defenses against emerging threats.

While other options reflect different aspects of computer security, they serve distinct functions. For instance, a firewall acts as a barrier between a trusted internal network and untrusted external networks, controlling incoming and outgoing traffic but not specifically targeting viruses. Malware refers to all types of malicious software, which can include viruses, making it a broader category rather than a specific tool. Adware is a type of software that automatically displays or downloads advertisements, which may not be malicious but can still affect performance and user experience.