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: Dental
[{'content': 'In young permanent teeth the best method of sensitivity testing for traumatized teeth is Carbondioxide snow which can go up to temperature of \nSelect and explain. \nA. —20°C, B. —30°C, C. —40°C, D. —78°C', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]