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': 'All of the following are true regarding removal of dentin smear layer during root canal preparation except: \nSelect and explain. \nA. Removal of dentin smear layer is done by using 37% EDTA, B. Dentin smear layer contains debris and microoroganism, C. Removal of dentin smear layer removes microorganism, D. Removal of dentin smear layer is enhanced by EDTA', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]