This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Physiology
[{'content': 'Which of the following enzymes is stable at acidic pH \nSelect and explain. \nA. Pepsin, B. Trypsin, C. Chymotrypsin, D. Carboxypeptidase', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Optimum pH for Pepsin- 1.6-3.2', 'role': 'assistant'}]