This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Ocular trauma , Subject name: Ophthalmology
what is deposited in Kyser-Fleischer ring- 
Select and explain. 
A. Copper, B. Lead, C. Mercury, D. Heme
A: Copper
Answer: A: Copper 
Explanation: *Kauser-Fleischer (KF) ring-> Copper deposition in Chalcosis or Wilson's disease *Fleischer ring-> Deposition of iron and is a sign of keratoconus