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': 'EDTA was introduced in endodontics by \nSelect and explain. \nA. Nygaard otsby, B. Hoshino, C. Bakland, D. Barnum', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Nygaard otsby introduced EDTA. Barnum introduced Rubber Dam. Hoshino advocated the use of triple antibiotic paste', 'role': 'assistant'}]