Joey experiences a continuous state of uncontrollable worry and tension. Most of the time, he feels jittery and breathless, even though he doesn't drink coffee. According to the DSM, this disorder is called:

A) panic attack.
B) posttraumatic stress disorder.
C) agoraphobia.
D) generalized anxiety disorder.

Joey's symptoms of continuous worry and tension, along with feeling jittery and breathless, are characteristic of generalized anxiety disorder (GAD). Panic attacks are sudden and intense bouts of fear and physical symptoms, while posttraumatic stress disorder (PTSD) involves experiencing trauma and often includes symptoms like flashbacks and avoidance behaviors. Agoraphobia involves a fear or avoidance of certain situations, but it alone does not encompass the other symptoms Joey is experiencing. Therefore, D is the best choice.