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: Microbiology
[{'content': 'Temperature required for holder method of pasteurization. \nSelect and explain. \nA. 63°c for 3 min, B. 72°c for 20 sec, C. 63°c for 20 min, D. 72°c for 30 sec', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Holder method - 63°c for\xa0 30 min\nFlash method -\xa072°c for 20 sec', 'role': 'assistant'}]