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': 'Arrange the following preparations in increasing order of their resisting area \nSelect and explain. \nA. A < B < C, B. B < A < C, C. C < B < A, D. C < A < B', 'role': 'user'}, {'content': 'Answer: C \nExplanation: The resisting area decreases as the preparation taper increases.\n\nFor a cylinder with no taper, the resisting area would cover half the axial walls (A).\nFor an deafly-tapered tooth preparation, the resisting area covers somewhat less than half the axial walls (B).\nAn over-tapered (20 degrees)\xa0preparation has only a small resisting area near the occlusal surface (C).', 'role': 'assistant'}]