This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Nutrition, Subject name: Medicine
[{'content': "Niacin deficiency occurs in all except- \nSelect and explain. \nA. Prolonged antibiotic use, B. Hanup's disease, C. Carcinoid syndrome, D. Isoniazid use", 'role': 'user'}, {'content': 'Answer: D \nExplanation: isoniazid act as chemical antagonist to pyridoxine causing pyridoxine deficiency Ref Harrison 20th edition pg 78', 'role': 'assistant'}]