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: Radiology
[{'content': "A neonate has a mass in kidney. USG shows hypoechoic shadow. The most likely diagnosis is: \nSelect and explain. \nA. Wilm's tumour, B. Neuroblastoma, C. Mesonephrohlastic tumour, D. Adenoma", 'role': 'user'}, {'content': 'Answer: C \nExplanation: Ans. Mesonephrohlastic tumour', 'role': 'assistant'}]