This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Adrenal Cortex and Medulla, Subject name: Pathology
[{'content': "The most common cause of Addison's disease is:-- \nSelect and explain. \nA. Autoimmune adrenalitis, B. Meningococcal septicemia, C. Malignancy, D. Tuberculosis", 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ans. is \'a\' Autoimmune adrenalitis " In early series, tuberculosis was responsible for 70 to 90% of cases, but the most frequent cause now is idiopathic atrophy, and an autoimmune mechanism is probably responsible". - Harrison, 15/e, P 2098Remember MC cause of Addison\'s ds* - Autoimmune adrenalitisMC cause of Addison\'s ds in India* - TB (API, 6/e, p 972)', 'role': 'assistant'}]