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: Biochemistry
Which is an omega-9 fatty acid ? 
Select and explain. 
A. Arachidonic acid, B. Oleic acid, C. Linolenic acid, D. Cervonic acid
B: Oleic acid
Answer: B: Oleic acid 
Explanation: Ans. is 'B i.e., Oleic acid