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 maxillary 1st permanent molar, the 2 obtuse angles are \nSelect and explain. \nA. Mesiolingual and mesiofacial, B. Mesiofacial and distolingual, C. Distofacial and mesiolingual, D. Distofacial and mesiofacial', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]