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
In a 9 - year old which permanent tooth surface will
show greatly increased caries incidence: 
Select and explain. 
A. Labial surface of central incisor, B. Occlusal surface of central incisor, C. Mesial surface of central incisor, D. Occlusal surface of lateral incisor
C: Mesial surface of central incisor
Answer: C: Mesial surface of central incisor 
Explanation: None