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
[{'content': 'Nerve compressed by aneurysm of posterior communicating artery is - \nSelect and explain. \nA. Occulomotor nerve, B. Optic nerve, C. Hypophysis cerebri, D. Trochlear nerve', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]