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: Medicine
Which of the following neoplasms is primary in the adrenal medulla: 
Select and explain. 
A. Pheochromocytoma, B. Eosinophilic adenoma, C. Arrthenoblastoma, D. None of the above
A: Pheochromocytoma
Answer: A: Pheochromocytoma 
Explanation: None