A man brings his 36- year- old wife to a new primary care doctor b/c she has lost patches of her hair recently. He notes that her last doctor sent her to a dermatologist, who felt that an underlying skin condition was unlikely. In a private exam room without her husband present, she says that she secretly pulls out her hair in clumps to relieve tension. The act of pulling her hair brings her relief. She denies changes in mood, sleep, concentration,, or energy level. What is the likely diagnosis?

A. Generalized anxiety disorder.
B. Major depressive disorder.
C. Tic disorder.
D. Trichotillomania