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': 'Minimum thickness of calcium hydroxide required to protect near or actual pulp exposure is? \nSelect and explain. \nA. 2-3 mm, B. 0.5-1mm, C. 3-4mm, D. 5mm', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]