This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Cranial Nerve Disorders, Subject name: Medicine
[{'content': 'Which of the following nerve is first affected in berry aneurysm: \nSelect and explain. \nA. 3 rd nerve, B. 4th nerve, C. 5th nerve, D. 6th nerve', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ans.(a) 3rd nerveRef: Harrison 19th ed. /1784-85* Most common cranial nerve affected in unruptured berry aneurysm is the 3rd cranial nerve which will present as ipsilateral ptosis, diplopia and strabismus.', 'role': 'assistant'}]