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: Pathology
[{'content': 'Most common caries seen in primary 1st molar \nSelect and explain. \nA. Occlusal pitas and fissures, B. Proximal surface below contact point, C. Proximal surface above contact point, D. Buccal surface below height of contour', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]