Fact 1: Earthworm burrows help aerate soil, which is also good for plants.

Fact 2: Most species construct burrows.

Given the two facts above, answer the question "What do constructions by earthworms help to do?" with the following options: 
- compact soil
 - moisten soil
 - agriculture
 - to move people
 - relocation
 - aerate soil
 - survival
 - dry out soil


 

      aerate soil   