What is the difference between a computer virus and a worm?

What is the difference between a computer virus and a worm?

A.
A worm can deposit an illicit server, whereas a virus cannot.

B.
A virus can deposit an illicit server, whereas a worm cannot.

C.
A worm can replicate by itself, whereas a virus requires user action to replicate.

D.
A virus can replicate by itself, whereas a worm requires user action to replicate.

Explanation: