This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Lens, Subject name: Ophthalmology
Sunflower cataract is caused by 
Select and explain. 
A. Siderosis, B. Chalcosis, C. Lead intoxication, D. Silicosis
B: Chalcosis
Answer: B: Chalcosis 
Explanation: Chalcosis is copper alloy in the eye Refer: Khurana 6th edition page number 194