Charlie$$s computer is attached to a network at work. One afternoon, Ralph, the company$$s IT specialist, asks Charlie and the rest of the staff to shut down their computers when they leave work so that he can disable the firewall and reset the network$$s security settings. The next day, when Charlie gets to work, he realizes that his computer$$s memory has been erased, along with the memory of all of his colleagues$$ computers. What happened?

Select answer from the options below

The network was damaged by a Trojan horse.

The network was damaged by spyware.

The network was damaged by a worm.

The network was damaged by a virus.