Which of the following contribute to the formation of clouds?

choose one or more:
a. air supersaturated with water
b. air temperatures below freezing
c. air that has not reached its dewpoint
d. air pollution from human activities
e. very small solid particles suspended in the air

Explanation: Clouds form when water vapor condenses in the atmosphere due to adiabatic cooling; air becomes saturated and there must be a surface, condensation nuclei (tiny particles such as microscopic dust, smoke) acts as surfaces on which water vapor can condense

ń, wǒ shuō yīngyǔ, dàn wǒ huì shuō qítā yǔyán, rú xībānyá yǔ fǎyǔ yìdàlì yǔ hé pǔtōnghuà, suǒyǐ bùyào pànduàn, dànshì