Answer:
The preferable words for the fill in the blanks will be -
Annelids, arthropods, cnidarians.
Explanation:
1. Annelids have a segmented body, for that, they are also known as segmented worms, have a closed circulatory system.
2. Arthropods have jointed appendages and an exoskeleton that must be shed to permit growth.
3. Cnidarians exhibit two radial body forms, the polyp, and the medusa, and use stinging cells to capture prey.