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: Social & Preventive Medicine
[{'content': 'Relative humidity is determined by \nSelect and explain. \nA. Kata thermometer, B. Anemometer, C. Sling psychrometer, D. Gardbad apparatus', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]