Why do cloud droplets not fall immediately as rain after they form?

Correct answer: They are very small and can remain suspended in air currents

Correct answer: B. Cloud droplets form when water vapour condenses, but the first droplets are extremely small. Their small mass means that their downward gravitational pull is weak, while air resistance and rising or turbulent air currents can keep them suspended inside the cloud. For a droplet to fall as rain, it generally has to grow larger and heavier. Growth can occur when droplets collide and combine, or through processes involving ice crystals and supercooled droplets in suitable clouds. Once a drop becomes large enough, gravity overcomes the upward effects of air movement and it falls as precipitation. A is incorrect because condensation changes vapour into liquid droplets, not immediately back into gas. C is incorrect because cloud water does not turn into rock. D is incorrect because cloud droplets do not create zero air pressure. B correctly explains both their small size and the role of air currents. Memory cue: clouds can hold tiny droplets; rain begins when droplets grow heavy enough.