This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: vitamins, Subject name: Biochemistry
Which of the following is the major source of Vitamin D 
Select and explain. 
A. Milk, B. Oily fish, C. Egg yolk, D. Sunlight
D: Sunlight
Answer: D: Sunlight 
Explanation: Vitamin D is not strictly a vitamin since it can be synthesized in the skin, and under most conditions, this is the major source of the Vitamin D. Ref : Biochemistry by U. Satyanarayana 3rd edition Pgno : 123