You are presented with the question "What helps soil breathe?" and the following answer choices: 
- the circulatory system
 - gasoline
 - loose dirt
 - temperature
 - evaporation
 - Exfoliation
 - aeration
 - bacteria

Now knowing that earthworm burrows help aerate soil, which is also good for plants and earthworms help soils breathe, choose the best answer.


 

       aeration  