This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Cornea, Subject name: Ophthalmology
K F Ring is seen in- 
Select and explain. 
A. Chalcosis, B. Sarcoidosis, C. Tuberous Sclerosis, D. VKH Syndrome
A: Chalcosis
Answer: A: Chalcosis 
Explanation: Ans. is 'a' i.e., Chalcosis * Kayser-Fleischer (KF) ring - Copper deposition in Chalcosis or Wilson's disease* Fleischer ring - Deposition of iron and is a sign of keratoconus