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: Surgery
Most reliable investigation in bladder rupture is 
Select and explain. 
A. IVP, B. Cystoscopy, C. Retrograde cystogram, D. Catheterisation
C: Retrograde cystogram
Answer: C: Retrograde cystogram 
Explanation: None