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': 'Treatment of choice for old non-united fracture of shaft of femur \nSelect and explain. \nA. Compression plating, B. Bone grafting, C. Nailing, D. Compression plating with bone grafting', 'role': 'user'}, {'content': 'Answer: D \nExplanation: D i.e. Compression plating with bone grafting', 'role': 'assistant'}]