What would happen if condensation nuclei were completely absent from the atmosphere?

Correct answer: Cloud formation and ordinary precipitation would become very difficult or nearly stop

Correct answer: B. Condensation nuclei are tiny particles such as dust, sea-salt particles, or other aerosols on whose surfaces water vapour can begin forming liquid droplets or ice particles. These particles make cloud formation easier under ordinary atmospheric conditions. If they were completely absent, water vapour could still exist and evaporation would not automatically stop, but forming cloud droplets would require much greater supersaturation and would become extremely difficult. Consequently, ordinary cloud formation and precipitation would be greatly reduced or nearly absent. A is the opposite of the expected result. C is wrong because evaporation is driven mainly by energy and surface conditions. D is wrong because less precipitation would not directly raise groundwater. Memory cue: nuclei provide the “starting surfaces” for cloud droplets.