Correct Answer:

Coelenterata

Solution : The correct option is Coelenterata

Cnidaria , also known as Coelenterata, is a phylum of aquatic invertebrates that includes a varied collection of organisms distinguished by their specialised stinging cells called cnidocytes. These animals have a body structure with radial symmetry and a sac-like or cylindrical form. Cnidarians live in both saltwater and freshwater habitats. Corals, sea anemones and sea pens are all members of the Anthozoa class.