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': 'Sagittal split osteotomy is a procedure done in the\nmandibular: \nSelect and explain. \nA. Ramus, B. Body, C. Symphysis, D. Angle', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]