Jeffrey Is So Preoccupied by His Fear of Germs That

Jeffrey is so preoccupied by his fear of germs that he always keeps his car and apartment windows sealed tightly, and refuses to allow anyone into his apartment. He carries his own silverware, which he uses when he eats away from home, and washes his hands every time he touches anything that has been touched by someone else. Jeffrey would most likely be diagnosed with:

A) dissociative identity disorder.
B) schizophrenia.
C) obsessive-compulsive disorder.
D) cyclothymic disorder.