A technician receives a computer for repair with a work order stating, erratic behavior please resolve. Which of the following can be done to diagnose the problem?

A.
Replace all system components.

B.
Boot the system and run DEFRAG.

C.
Strip the system down to the essential components and systematically replace components until the system is stable.

D.
Treat the system as though the system were new and format the hard drive; load a base operating system and run burn-in routines.