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': 'An incipient carious lesion on an inter proximal surface\nis usually located \nSelect and explain. \nA. At the contact area, B. Facial to contact area, C. Gingival to contact area, D. Lingual to contact area', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]