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
Chalcosis is caused by 
Select and explain. 
A. Iron, B. Lead, C. Copper, D. Mercury
C: Copper
Answer: C: Copper 
Explanation: “Chalcosis refers to specific changes made by copper containing alloys in eye” Features of chalcosis are:
√ KF rings on descement membrane of cornea
√ Sunflower cataract
√ Golden brown metallic sheen plaques on the retinal pole