This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Enzymes, Subject name: Biochemistry
B-Carotene, precursor of vitamin A, is oxidatively cleaved by: 
Select and explain. 
A. b-Carotene dioxygenase, B. Oxygenase, C. Hydroxylase, D. Transferase
A: b-Carotene dioxygenase
Answer: A: b-Carotene dioxygenase 
Explanation: Ans. A. b-Carotene dioxygenaseCarotene is cleaved by b-carotene dioxygenase of intestinal cells to release 2 moles of retinal which is reduced to retinol.