This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Endocrinology, Subject name: Medicine
[{'content': 'DOC in adrenal insufficiency? \nSelect and explain. \nA. Hydrocoisone, B. Adrenaline 2012-13, C. Dexamethasone, D. Fludrocoisone', 'role': 'user'}, {'content': 'Answer: A \nExplanation: hydrocoisone is the mainstay of treatment. Dose of about 20_ 30 mg /d ( Harrison 17 pg 2264)', 'role': 'assistant'}]