A. Modifies directory table entries so that directory entries point to the virus code instead of the actual program.

B. Moves the MBR to another location on the RAM and copies itself to the original location of the MBR.

C. Moves the MBR to another location on the hard disk and copies itself to the original location of the MBR.

D. Overwrites the original MBR and only executes the new virus code.