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: Dental
[{'content': 'Single wavelength light is emitted by: \nSelect and explain. \nA. QTH, B. LED, C. Argon laser, D. PAC', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Argon laser light has wavelength of 470 nm which is monochromatic (single wavelength or frequency) in nature.\xa0\nIt produces an intensity of 200 to 300 mW.\n\n\u200bRef: Textbook of Operative Dentistry, Nisha and Amit Garg, 3rd edition, Pg no:277', 'role': 'assistant'}]