A autonomous agent that copies itself into one or more host programs, then propagates when the host is run, is best described as a:
A.
Trojan horse
B.
Back door
C.
Logic bomb
D.
Virus
Explanation:
A virus is a piece of software designed to infect a computer system. I can go into this further, but the answer is obvious.
Reference: Security + (SYBEX) page 76