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
Jafferson's fracture is the fracture of - 
Select and explain. 
A. Odontoid, B. C1, C. C2, D. C3
B: C1
Answer: B: C1 
Explanation: Jafferson's fracture is the most common type offracture of atlas (1).