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': 'Following instruments are used in: \nSelect and explain. \nA. Root apex filling, B. Perforation repair, C. Root canal filling, D. All of the above', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]