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 a 9 - year old which permanent tooth surface will\nshow greatly increased caries incidence: \nSelect and explain. \nA. Labial surface of central incisor, B. Occlusal surface of central incisor, C. Mesial surface of central incisor, D. Occlusal surface of lateral incisor', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]