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: Pharmacology
Metyrosin is used in ? 
Select and explain. 
A. Acromegaly, B. Cushing syndrome, C. Addison's disease, D. Pheochromocytoma
D: Pheochromocytoma
Answer: D: Pheochromocytoma 
Explanation: Ans: D PheochromocytomaRef: KDT 7/e p. 128, 129; Katzung rlth/e p. g4lRate limiting step (tyrosine hydrorylation) in synthesis of epinephrine is inhibited by metyrosine.