Question

which category? scyphozoa sea anemones true jellyfish corals

Explanation:

Scyphozoa is a class of the phylum Cnidaria. True jellyfish belong to the class Scyphozoa. Sea anemones are in the class Anthozoa, and corals are also in Anthozoa. So the correct match for Scyphozoa is true jellyfish.

Answer:

true jellyfish