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: Medicine
Which of the following is most likely to be affected in an anuerysm of posterior cerebral artery (PCA)? 
Select and explain. 
A. Hypophysis cerebri, B. Trochlear nerve, C. Oculomotor nerve, D. Optic nerve
C: Oculomotor nerve
Answer: C: Oculomotor nerve 
Explanation: None