Tommy Has Obsessions About Cleanliness and Is a Compulsive Hand

Tommy has obsessions about cleanliness and is a compulsive hand washer.Which of the following pieces of evidence best supports the view that his obsessive-compulsive disorder is related to operant conditioning?

A) Tommy's sworn enemy,Bobby,hardly ever washes his hands,so Tommy engages in the behavior compulsively to be as different as possible from Bobby.
B) Tommy sees his brother engage in compulsive hand washing,so he also engages in the same behavior.
C) Tommy experiences a large reduction in anxiety whenever he washes his hands,so he engages in the behavior whenever he becomes anxious.
D) Tommy believes that hand washing will prevent him from becoming sick,so he engages in the behavior compulsively.