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': 'PROTAPER NEXT is \nSelect and explain. \nA. Based on M wire NiTi Phase, B. Has reamer with alternative cutting edges, C. Has alternating wall contact points, D. Based on R phase NiTi', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Option B is for RACE\nOption C is for Endo sequence/ Real world endo\nTwisted file, K3XF etc uses R phase Ni Ti', 'role': 'assistant'}]