Concept: This requires matching phylum/class with a unique structural feature and a corresponding example.
Explanation: I. Nematoda ({Ancylostoma}) use renette glands for osmoregulation. II. Crustacea ({Palaemon}) use green glands (or antennal glands) for excretion. III. Cephalopoda ({Sepia}) use an ink gland for defense. IV. Echinoidea ({Echinus}) have the Aristotle's lantern, a complex chewing apparatus. All four combinations are correct.