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
Treatment option for keratoconus includes: 
Select and explain. 
A. Spectacles, B. Contact lens, C. Kerotoplasty, D. ALL
D: ALL
Answer: D: ALL 
Explanation: A. i.e. Spectacles; B. i.e. Contact lens; C. i.e. Keratoplasty