This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Urinary tract, Subject name: Pediatrics
Most common cause of abdominal mass in neonates is 
Select and explain. 
A. Neuroblastoma, B. Wilm's tumor, C. Distended bladder, D. Multicystic dysplastic kidneys
D: Multicystic dysplastic kidneys
Answer: D: Multicystic dysplastic kidneys 
Explanation: Multicystic dysplastic kidney(MCDK) is a condition that results from the malformation of the kidney during fetal development. The kidneyconsists of irregular cysts of varying sizes. Multicystic dysplastic kidney is a common type of renal cystic disease, and it is a cause of an abdominal mass in infants. Reference: GHAI Essential pediatrics, 8th edition