[单选题]
Supersaturation occurs +-f .fjlpx;6ny51h7ob oey awinze p,5(oodir 0 air when the
A. relative humidity is 100% and the temperature increases.
B. relative humidity is less than 100% and the temperature increases.
C. relative humidity is less 100% and the temperature decreases.
D. relative humidity is 100% and the temperature decreases.
