Fact 1: Roundworms make up the phylum Nematoda.

Fact 2: Within the Nematoda, a range of reproductive systems occur.

Given the two facts above, answer the question "where does a range of reproductive systems occur?" with the following options: 
- exoskeletons
 - Plant reproduction
 - h2o
 - shrub beds
 - within roundworms
 - clouds
 - Most plants
 - gastropod shells


 

     within roundworms    