This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Spinal Injuries, Subject name: Orthopaedics
[{'content': "Regarding Hangman's fracture true is: \nSelect and explain. \nA. High post-admission mortality, B. Most common axis fracture, C. Surgical treatment is necessary, D. Union almost always occurs", 'role': 'user'}, {'content': 'Answer: D \nExplanation: (d) Union almost always occurs- Successful healing of C2 traumatic spondylolisthesis is reported to approach 95%. This is most commonly achieved with non-operative measures, even in the presence of displacement of pars inter-articularis.', 'role': 'assistant'}]