单选题The amount of moisture in a given sample of air, when compared with the amount of moisture the air could hold if totally saturated at the existing temperature of the sample, is called （）.Aabsolute humidityBspecific humidityCeffective humidityDrelative humidity
单选题
The amount of moisture in a given sample of air, when compared with the amount of moisture the air could hold if totally saturated at the existing temperature of the sample, is called （）.
A
absolute humidity
B
specific humidity
C
effective humidity
D
relative humidity
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