A(n) ________ is a persistent, unwanted thought.

A) obsession
B) compulsion
C) delusion
D) hallucination

Obsessions are persistent, unwanted, and intrusive thoughts, images, or impulses that cause distress and anxiety. Compulsions, on the other hand, are repetitive behaviors or mental acts performed in response to an obsession, often in an attempt to neutralize the anxiety caused by the obsession. Delusions and hallucinations are both types of psychotic symptoms, but they are not necessarily related to obsessive-compulsive disorder (OCD).