Keith Often Hears Voices That Tell Him That He Is

Keith often hears voices that tell him that he is a very bad person.Although he strains and struggles to "hear" where these voices are coming from,there are in fact no voices to hear.They are originating inside of his mind,and he experiences them as a sensory event.Keith is having a symptom of schizophrenia called a(n) __________.

A) hallucination
B) delusion
C) negative symptom
D) hyperalgia