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': 'In anterior teeth, the starting location for access cavity is the center of the anatomic crown on lingual surface at \nSelect and explain. \nA. Angle to it, B. In line to it, C. Perpendicular to it, D. All of the above', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]