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
[{'content': 'A neonate presenting with ascites is diagnosed having urinary ascites. What is the most common cause: \nSelect and explain. \nA. Bilateral PUJ obstruction, B. Infant polycystic kidney disease, C. Posterior urethral valve, D. Meatal stenosis', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]