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': 'IVP of polycystic kidney disease shows – \nSelect and explain. \nA. Cobra head, B. Dropping lily, C. Flower base appearance, D. Spider leg deformity', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]