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': 'A 10 degree decrease in temperature causes decrease in cerebral metabolic rate by \nSelect and explain. \nA. 10%, B. 30%, C. 50%, D. 70%', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Metabolism reduces by 6.7% for every 10C fall in temperature.', 'role': 'assistant'}]