Given the following reasoning and answer, what was the question? Roundworms make up the phylum Nematoda. Within the Nematoda, a range of reproductive systems occur. A range of reproductive systems occur in roundworms.
 The answer: (D)
The question What has a range of sexual reproductive systems? 
Options:
- (A) Computer systems.
- (B) Most plants
- (C) animals
- (D) Roundworms.
- (E) mammals
- (F) Art reproductions.
- (G) insects
- (H) Stuffed toy bears.