Giles is the network administrator for his company, a graphics design company based in Dallas. Most of the network is comprised of Windows servers and workstations, except for some designers that prefer to use MACs. These MAC users are running on the MAC OS X operating system. These MAC users also utilize iChat to talk between each other. Tommy, one of these MAC users, calls Giles and says that his computer is running very slow. Giles then gets more calls from the other MAC users saying they are receiving instant messages from Tommy even when he says he is not on his computer. Giles immediately unplugs Tommy’s computer from the network to take a closer look. He opens iChat on Tommy’s computer and it says that it sent a file called latestpics.tgz to all the other MAC users. Tommy says he never sent those files. Giles also sees that many of the computer’s applications appear to be altered. The path where the files should be has an altered file and the original application is stored in the file’s resource fork.

What has Giles discovered on Tommy’s computer?

A.
He has discovered OSX/Chat-burner virus on Tommy’s computer

B.
Giles has found the OSX/Leap-A virus on Tommy’s computer

C.
This behavior is indicative of the OSX/Inqtana.A virus

D.
On Tommy’s computer, Giles has discovered an apparent infection of the OSX/Transmitter.B virus

Explanation:
OSX.Leap.A is a worm that targets installs of Macintosh OS X and spreads via iChat Instant Messenger program.
http://www.symantec.com/security_response/writeup.jsp?docid=2006-021614-4006-99