This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Endocrinology, Subject name: Biochemistry
Sterols are metabolized to 
Select and explain. 
A. Coenzyme A, B. VIt A, C. Vit D, D. Vit E
C: Vit D
Answer: C: Vit D 
Explanation: Vitamin D is derived from 7-dehydrocholesterol by the action of UV radiations 7 dehydrocholesterol, an intermediate of a minor pathway of cholesterol synthesis The cis double bond is isomerized to a trans double bond to give rise to vitamin D3 or cholecalciferol Ref: DM Vasudevan, 7th edition, page no: 469