What type of software is designed to replicate itself and spread to other computers?

The type of software designed to replicate itself and spread to other computers is a virus. A virus is a malicious program that attaches itself to legitimate software or files on a computer system, enabling it to replicate and propagate to other systems, usually without the user’s knowledge. This self-replication is typically accomplished by infecting other files when a user executes an infected program, leading to additional infections and potential damage to systems.

In contrast, spyware focuses on gathering information about users without their consent, typically for marketing purposes. It does not replicate itself. A Trojan Horse pretends to be a legitimate software application but does not have the ability to replicate itself; its purpose is often to breach security and create vulnerabilities. Adware, while potentially intrusive and annoying, primarily serves to display advertisements and collect user data but does not replicate itself like a virus. The distinctive feature of a virus is its ability to replicate and spread, which is why it is the correct answer in this context.