This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Tryptophan metabolism detail, Subject name: Biochemistry
[{'content': 'Xanthoproteic test is used for - \nSelect and explain. \nA. Ketone bodies, B. Bile salts, C. Amino acids, D. Reducing sugars', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Xanthoproteic test is a color (yellow) reaction of proteins This test is Positive for aromatic amino acids only. Note: Xanthurenic acid is the metabolite in the metabolism of tryptophan.', 'role': 'assistant'}]