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: Pediatrics
[{'content': 'One-year-old male child presented with poor urinary stream since birth. The investigation of choice for evaluation is – \nSelect and explain. \nA. Voiding cystourethrography (VCUG), B. USG bladder, C. Intravenous urography, D. Uroflowmetry', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Poor urinary stream since birth suggests urinary tract obstruction (usually intravesical).\nMost common cause of urinary tract obstruction in a male child is → posterior urethral valve.\nAnd the best diagnostic method for posterior urethral valve is voiding cystourethrogram.', 'role': 'assistant'}]