You are presented with the question "Earthworms help form and add what to soil" and the following answer choices: 
- Sediment
 - organic material
 - Converting waste.
 - bacteria
 - heat
 - Chemical energy
 - grass
 - acidity

Now knowing that earthworms are important deposit feeders that help form and enrich soil and tulips perform best in a sandy, organically enriched soil, choose the best answer.


 

  organic material       