Which of the Following Statements Describes Locomotion in Nematodes

Which of the following statements describes locomotion in nematodes?

A) Rhythmically beating cilia move the animal forward.
B) Circular and longitudinal muscles work against each other and the pseudocoelom to change the shape of the animal, moving it forward.
C) Longitudinal muscles contract.
D) A series of hairs that project backward engage the substrate; back-and-forth movements propel the animal forward.
E) Water expelled through special ducts moves the animal forward.