Roundworms make up the phylum Nematoda, and within the Nematoda, a range of reproductive systems occur. Given these facts, where does a range of reproductive systems occur among the following options:
- exoskeletons
 - Plant reproduction
 - h2o
 - shrub beds
 - within roundworms
 - clouds
 - Most plants
 - gastropod shells


 

     within roundworms    