This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Kidney, Subject name: Pediatrics
Investigation of choice in VUR 
Select and explain. 
A. Ultrasound, B. MRI, C. Voiding cystourethrogram, D. Cystoscopy
C: Voiding cystourethrogram
Answer: C: Voiding cystourethrogram 
Explanation: c. Voiding cystourethrogram(Ref: Nelson's 20/e p 2562-2567, Ghai 8/e p 485-486)The most useful process for conclusive diagnosis of VUR is micturating cystourethrogram (MCU)MCU demonstrates the grade of reflux as well as urethral anatomy.Radionuclide imaging is sensitive at detecting reflux but does not demonstrate anatomic details