This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Miscellaneous, Subject name: Ophthalmology
[{'content': 'Laser used in LASIK- \nSelect and explain. \nA. Excimer, B. Argon, C. Holmium, D. Nd-yag', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Excimer (excited dimer) lasers are used in photo refractive keratotomy (PRK), LASIK and phototherapeutic keratectomy. Mechanism : produce UV light of very sho wavelength which breaks chemical bonds of biologic materials, conveing them into small molecules that diffuse away. Ref: AK Khurana 6thE pg462', 'role': 'assistant'}]