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: Radiology
In spondolysthesis following radiological features seen – a) Scotty dogb) Scotty dog wearing a collarc) Beheaded scotty dog terrier signd) Nepolean sign 
Select and explain. 
A. ab, B. bc, C. cd, D. ac
C: cd
Answer: C: cd 
Explanation: None