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: ENT
[{'content': 'Which of the following is the earliest sign to appear in acoustic neuroma? \nSelect and explain. \nA. Diplopia, B. Ptosis, C. Diminished corneal sensitivity, D. Congestion of conjunctiva', 'role': 'user'}, {'content': 'Answer: C \nExplanation: The first symptom of an acoustic neuroma is hearing loss and the first sign diminished corneal sensitivity. Acoustic neuroma affects the trigeminal nerve, causing a diminished or absent corneal reflex, tinnitus, and unilateral hearing impairment. Facial palsy and anesthesia, palate weakness, and signs of cerebellar dysfunction may result if the tumor impinges on the adjacent cranial nerves, brain stem, and cerebellum.', 'role': 'assistant'}]