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
Most impoant investigation for posterior urethralvalve is 
Select and explain. 
A. Urethroscopy, B. IVP, C. Retrograde cystogram, D. Micturating cystogram (MCU)
D: Micturating cystogram (MCU)
Answer: D: Micturating cystogram (MCU) 
Explanation: D i.e. MCU