You are presented with the question "Springs can be fed by what?" and the following answer choices: 
- mechanical waves
 - vernal equinox
 - precipitation
 - rainfall
 - digestive track
 - water vapor
 - aqueous solution
 - carnivores

Now knowing that some precipitation that falls on land may soak into the ground, becoming groundwater and wells are drilled into groundwater and springs are fed by groundwater, choose the best answer.


 

   precipitation      