Please answer the following question: Answer the following question given this paragraph: Roundworms make up the phylum Nematoda. They have a pseudocoelom and hydrostatic skeleton. Their body is covered with tough cuticle. Free-living roundworms are found mainly in freshwater habitats. Parasitic roundworms have a variety of hosts, including humans. Q: What has a pseudocoelom and hydrostatic skeleton? Choices: - vertebrates - omnivores - gymnosperms - roundworms A:
A:
roundworms