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: Surgery
Most common site of cerebral aneurysm is: 
Select and explain. 
A. Anterior communicating aery, B. Posterior communicating aery, C. Middle cerebral aery, D. None of the above
A: Anterior communicating aery
Answer: A: Anterior communicating aery 
Explanation: Prevalence of Cerebral Aneurysm by Location: Anterior circulation 85% 30% Anterior communicating aery 25% Posterior communicating aery 20% Middle cerebral aery bifurcation 10% Other Posterior circulation 15% 10% Basilar aery, most frequently at the basilar tip 5% Veebral aery, usually at the posterior inferior cerebellar aery Ref: Schwaz's principle of surgery 9th edition, chapter 42.