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': 'Glass workers cataract is caused by exposure to which of the following? \nSelect and explain. \nA. Infrared rays, B. Ultraviolet rays, C. X - rays, D. Lead', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Prolonged exposure to infrared rays can cause discoid posterior subcapsular opacity and is typically seen in people working in glass industry. Ref: A K Khurana, 2nd Edition, Page 195.', 'role': 'assistant'}]