What type of malware is primarily designed to harm a network or system?

The correct response is that a virus is primarily designed to harm a network or system. A virus is a type of malware that attaches itself to a legitimate program or file and can replicate itself to spread to other computers. When executed, it can corrupt or delete data, degrade system performance, and even allow unauthorized access to sensitive information. This malicious intent is what sets viruses apart as aggressive forms of malware aligned with the goal of harming the system.

In contrast, spyware is focused on collecting information from users without their knowledge and does not primarily exist to damage systems. A Trojan Horse disguises itself as a legitimate application but is mainly about creating backdoors for attackers rather than directly causing harm. Adware typically generates unwanted advertisements and may diminish performance but is often viewed as less harmful compared to other types of malware. Thus, viruses represent the most direct threat to the integrity and functionality of systems and networks.