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

The correct answer is a worm. A worm is a specific type of malware that is designed to replicate itself and spread to other computers without the need for a host program, which distinguishes it from viruses. Worms can self-replicate by exploiting vulnerabilities in software or network protocols, allowing them to move across networks and infect multiple devices independently.

In contrast, a virus must attach itself to a host file or program to execute and propagate, requiring user action (such as opening a file) to spread. Spyware is designed to gather information and monitor user activity without their knowledge but does not focus on self-replication. A rootkit is a type of malware designed to gain unauthorized access to a computer and maintain control over it, often with stealth, but it does not replicate itself. This differentiation highlights why worms are defined by their independent ability to spread, making them particularly concerning in network security.