Final answer:
The members of the phylum Nematoda are morphologically diverse and diverse in their way of life. They include both free-living and parasitic species and have a complete digestive system.
Step-by-step explanation:
The accurate description of the phylum Nematoda is that its members are morphologically diverse, diverse in way of life. Nematodes, also known as roundworms, are triploblastic organisms with a pseudocoelom and a circular cross-section. They include both free-living and parasitic species and have a complete digestive system.