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: Physiology
[{'content': 'What amount of Tryptophan produces 1gm of niacin? \nSelect and explain. \nA. 40mg, B. 50mg, C. 60mg, D. 70mg', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Niacin (1 mg of niacin is formed from 60 mg of tryptophan).', 'role': 'assistant'}]