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
In Spondylolisthesis, which of the following is NOT useful investigation? 
Select and explain. 
A. Anteroposterior X-ray, B. Lateral view X-ray, C. CT, D. MRI
A: Anteroposterior X-ray
Answer: A: Anteroposterior X-ray 
Explanation: (a)-AP view will show changes only in last stages-inverted Napoleon hat sign all other are more important for diagnosis and management. CT and MRI are required in all cases.