Mireille began having brief episodes of overwhelming anxiety about a year ago. She doesn't know what causes them, but she has had them in the grocery store, at busy restaurants and once while driving. Her heart pounds, she has difficulty breathing and sometimes she feels like her body no longer belongs to her. She is afraid she will go crazy or have a heart attack. Based on this information, Mireille may have?
A. Obsessive-compulsive disorder
B. A somatoform disorder
C. A dissociative disorder
D. A panic disorder