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': 'In which one of the following femoral fractures is Avascular necrosis common? \nSelect and explain. \nA. Perochanteric, B. Transcervical, C. Sub-Trochanteric, D. Shaft of femur', 'role': 'user'}, {'content': 'Answer: B \nExplanation: B i.e. Trans cervical', 'role': 'assistant'}]