What type of malware is specifically designed to replicate itself?

The correct answer, a virus, is a specific type of malware that has the capability to replicate itself by attaching its code to other programs or files. When a host program or file that contains the virus is executed, it can trigger the replication process, allowing the virus to spread to other systems and files. This self-replicating nature is a defining characteristic of viruses, distinguishing them from other types of malware.

In contrast, spyware is designed to collect information from a user's system without their knowledge, while adware typically displays advertisements and may also collect user data but does not replicate itself. A Trojan is a type of malware that disguises itself as legitimate software to trick users into executing it, but it does not replicate itself in the way that a virus does. Overall, the defining feature of a virus is its ability to replicate and spread, making it the correct answer to the question.