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: Orthopaedics
[{'content': "Hangman's fracture is fracture of C2 - \nSelect and explain. \nA. Dens fracture, B. Lamina, C. Pars interarticularis, D. Spinous process", 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]