This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Medicine
[{'content': 'Disease due to deficiency of B Complex vitamins is \nSelect and explain. \nA. Pellagra, B. Night blindness, C. Osteomalacia, D. Spinocerebellar ataxia', 'role': 'user'}, {'content': "Answer: A \nExplanation: Pellagra Niacin deficiency (B complex)Night blindnessVitamin A deficiencyOsteomalacia Vitamin D deficiencySpinocerebellar ataxiaVitamin E deficiency(ref:Harrison's 17/e p442)", 'role': 'assistant'}]