What is the simple meaning of dew point?

Correct answer: The temperature at which air becomes saturated

Correct answer: C, the temperature at which air becomes saturated. Dew point is a temperature, not a place or an event involving the end of rain. When air containing water vapour cools to its dew point, it becomes saturated with respect to that vapour. Further cooling, or suitable conditions, can then lead to condensation and the formation of dew, fog, or other water droplets. A is wrong because dew point does not mean that air is completely dry; it means the opposite—the air has reached saturation. B is wrong because the stopping of rainfall does not define a temperature. C is correct because it gives the basic definition. D is wrong because the meeting place of rivers is unrelated to atmospheric moisture. The exact dew point depends on the amount of water vapour already present, so it is not necessarily the same in every air mass. Memory cue: dew point is the saturation temperature at which dew may begin.