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
Cranial nerve most commonly involved in posterior communicating aery aneurysm is 
Select and explain. 
A. Oculomotor, B. Facial, C. Optic, D. Trigeminal
A: Oculomotor
Answer: A: Oculomotor 
Explanation: . *a third nerve palsy may be present due to local pressure from an aneurysm of the posterior communicating aery. Ref Harrison20th edition pg 2456