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
Xerosis is seen in: September 2006 
Select and explain. 
A. Vitamin A deficiency, B. Vitamin B deficiency, C. Vitamin C deficiency, D. Vitamin D deficiency
A: Vitamin A deficiency
Answer: A: Vitamin A deficiency 
Explanation: Ans. A: Vitamin A deficiency