This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Vitamins and Minerals, Subject name: Biochemistry
[{'content': 'Which of the following vitamin is metabolically produced by the body? \nSelect and explain. \nA. Biotin, B. Vitamin K, C. Niacin, D. Pyridoxine', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Essential amino acid tryptophan can be conveed into Niacin (B3) in our body (60 mg tryptophan = 1 mg Niacin). As, it can be synthesised in the body by metabolism, strictly speaking, Niacin is not a Vitamin.', 'role': 'assistant'}]