This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: C.N.S, Subject name: Medicine
Lateral medullary syndrome is caused by thrombosis of- 
Select and explain. 
A. Anterior inferior cerebral aery, B. Posterior interior cerebellar aery, C. Veebral aery, D. Basilar aery
C: Veebral aery
Answer: C: Veebral aery 
Explanation: * Dorsolateral pa of the medulla is suplied by posterior inferior cerebellar aery ,which usually a branch of veebral aery *thrombosis of posterior inferior cerebellar aery ,therfore effects a wedge shaped area on the dorsolateral aspects of medulla and the inferior surface of cerebellum produce lateral medullary syndrome of wallenberg. Ref Harrison20th edition pg 2435