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': 'Normal intrapulp pressure is \nSelect and explain. \nA. 10mm Hg, B. 5mm Hg, C. 7mm Hg, D. 15mm Hg', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]