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': 'Treatment option for keratoconus includes: \nSelect and explain. \nA. Spectacles, B. Contact lens, C. Kerotoplasty, D. ALL', 'role': 'user'}, {'content': 'Answer: D \nExplanation: A. i.e. Spectacles; B. i.e. Contact lens; C. i.e. Keratoplasty', 'role': 'assistant'}]