You are presented with the question "what process must occur to form clouds?" and the following answer choices: 
- thunderstorms
 - Movement of an air mass
 - evaporation
 - nimbus
 - snow
 - water evaporating
 - chemical changes
 - cloudy and rainy weather

Now knowing that clouds are formed by water vapor rising into colder regions of the atmosphere and condensing and this water evaporates into water vapor and rises up into the atmosphere, choose the best answer.


 

      water evaporating   