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': 'The gingival finish Line on a tipped molar should be \nSelect and explain. \nA. Shoulder, B. Chamfer, C. Knife edge, D. Feather edge', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]