This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Psychiatry
Lithium is not used in treatment of which of the following? 
Select and explain. 
A. Major depression, B. Vascular headache, C. Neutropenia, D. Generalized anxiety disorder
D: Generalized anxiety disorder
Answer: D: Generalized anxiety disorder 
Explanation: Generalized anxiety disorder