This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Spinal Injury, Subject name: Orthopaedics
[{'content': "Jefferson's fracture is: \nSelect and explain. \nA. Fracture of Axis, B. Fracture of Atlas, C. Due to fracture of traumatic spondylolisthesis of C2 over C3, D. Avulsion fracture of C7", 'role': 'user'}, {'content': 'Answer: B \nExplanation: Fractures of Spine Jefferson Fracture Burst fracture of C1(ATLAS) Mn: JAT Jefferson-ATlas Avulsion fracture of C7 is known as-Clay shoveller fracture Fracture of pedicle of C2 and spondylolisthesis over C3 is hangmanns fracture.', 'role': 'assistant'}]