You are presented with the question "What can change atmospheric nitrogen into a form used by plants?" and the following answer choices: 
- Conifers
 - mutations
 - Collagen
 - earthworm
 - sugar
 - Enzymes
 - spores
 - wind

Now knowing that bacteria in soil convert atmospheric nitrogen into a form usable by plants and spores are a dormant form of bacteria, choose the best answer.


 

       spores  