Fact 1: Roundworms may be free-living or parasitic. Fact 2: Roundworms make up the roundworm phylum, Nematoda. Given the two facts above, answer the question "What can the phylum Nematoda be?" with the following options: - dangerous - parasitic - horses - meiosis - more abundant - graptolites - homogenous - phytoplankton
parasitic