If air is saturated and water is available at the surface, why will evaporation still be very low?

Correct answer: Because the air is already holding maximum water vapour

The correct answer is A. Saturated air is already holding approximately the maximum water vapour it can hold at its current temperature. Evaporation adds vapour to the air, so when the air has almost no remaining capacity, the net rate of evaporation becomes very low. Individual molecules may still leave the water surface, but condensation can occur at nearly the same time, so there is little overall increase in vapour. B is wrong because water temperature is not always zero; evaporation depends on the actual temperature and other conditions. C is wrong because evaporation does not require the oxygen supply to be exhausted. D is wrong because sunlight generally supplies energy and may increase evaporation; it does not destroy water vapour. A change in wind or drier air could increase evaporation by replacing saturated air with air that has more capacity. Memory cue: saturated air is like a full container—it has almost no room for additional vapour.