This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Environment and health, Subject name: Social & Preventive Medicine
Sling psychrometer is used for measuring - 
Select and explain. 
A. Air velocity, B. Rain fall, C. Median radiant temperature, D. Relative humudity
D: Relative humudity
Answer: D: Relative humudity 
Explanation: Relative humidity of air may be obtained from the readings of sling psychrometer /whirling psychrometer. Park's Textbook of Preventive and Social Medicine, 25th Edition, Pg 809