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': 'Laser used in LASIK ? \nSelect and explain. \nA. Yag, B. Diode, C. Excimer, D. None', 'role': 'user'}, {'content': "Answer: C \nExplanation: Ans. is 'c' i.e., Excimer 3 PRK, PTK, LASIK and LASEK use excimer (argon fluoride) laser.", 'role': 'assistant'}]