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: Ophthalmology
[{'content': 'Neuroparalytic keratitis is due to which cranial nerve: \nSelect and explain. \nA. 3rd nerve, B. 5th nerve, C. 6th nerve, D. 7th nerve', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans. 5th nerve', 'role': 'assistant'}]