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: Ophthalmology
[{'content': 'Sunflower cataract is associated with the inborn error of metabolism of which of the following? \nSelect and explain. \nA. Iron, B. Nickel, C. Copper, D. Zinc', 'role': 'user'}, {'content': "Answer: C \nExplanation: Sunflower cataract is associated with the inborn error of copper metabolism (Wilson's disease). Ref: A K Khurana, 5th Edition, Page 91", 'role': 'assistant'}]