You are presented with the question "what do organisms aerate?" and the following answer choices: 
- magma
 - moles.
 - roots
 - Carbon
 - volcanoes
 - cell walls
 - soil
 - Crops

Now knowing that earthworm burrows help aerate soil, which is also good for plants and earthworms and other soil organisms keep the soil healthy, choose the best answer.


 

       soil  