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
A male child presents with repeated urinary infections and failure to gain weight. A MCU was carried out as shown in plate, most probable diagnosis is? 
Select and explain. 
A. Posterior urethral valve, B. Meatal stenosis, C. Bladder diverticula, D. Bladder polyp
A: Posterior urethral valve
Answer: A: Posterior urethral valve 
Explanation: a. Posterior urethral valve(Ref: Nelson's 20/e p 2562-2567, Ghai 8/e p 485-486)Voiding cystourethrogram in an infant with posterior urethral valves showing the dilation of the prostatic urethra and the transverse linear filling defect corresponding to the valves.