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
Orange - skin cornea is due to 
Select and explain. 
A. Siderosis, B. Chalcosis, C. Mustard gas, D. Lindane
C: Mustard gas
Answer: C: Mustard gas 
Explanation: Mustard gas is Dichloroethyl sulphide causes orange skin cornea.