The looseness of soil has a positive impact on a plant 's roots' growth in that soil, and many orchids are rewarding indoor plants. Given these facts, what sees a positive impact on root growth due to looseness of soil among the following options:
- Roundworms
 - Conifers
 - humans
 - h2o
 - orchids
 - Earthworms
 - mussels
 - teeth


 

     orchids    