13. A 52-year-old man complains of a sudden onset of severe, stabbing pain in the left jaw and cheek that subsides in less than a minute. He is pain-free during the intervals between attacks. Activities such as combing his hair and shaving can cause the onset of this facial pain. He is otherwise healthy. The most likely diagnosis is (A) trigeminal neuralgia (B) atypical facial pain (C) postherpetic neuralgia (D) vascular facial pain