This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Ear, Subject name: ENT
[{'content': 'In acoustic neuroma, cranial nerve to be involved earliest is \nSelect and explain. \nA. 5, B. 7, C. 9, D. 10', 'role': 'user'}, {'content': 'Answer: A \nExplanation: The earliest cranial nerve to be involved is V nerve causing reduced corneal sensitivity. Ref: Textbook of diseases of ENT, PL Dhingra, 7th edition, pg no. 125', 'role': 'assistant'}]