This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Brain , Subject name: Anatomy
[{'content': 'Berry aneurysm of the posterior communicating aery causes compression of \nSelect and explain. \nA. Optic nerve, B. Oculomotor, C. Trochlear nerve, D. Hypophysis cerebri', 'role': 'user'}, {'content': "Answer: B \nExplanation: Berry aneurysm in the vicinity of posterior communicating aery can compress the third carnial nerve and cause oculomotor nerve palsy Aneurysms of superior cerebellar aery or tip of the basilar aery can also compress the oculomotor nerve and produce its palsy Berry aneurysm on the internal carotid aery (near its termination) compresses the lateral aspect of optic chiasma and hence damages the visual information from the ipsilateral nasal visual field. Ref: Gray's 39e/p-22", 'role': 'assistant'}]