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: Surgery
[{'content': "The extraoral X-ray view required for a fracture of mandible is: \nSelect and explain. \nA. Submentovertex, B. Posterioanterior, C. Water's, D. Towne's", 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]