Final answer:
An animal with radial cleavage and enterocoely is a deuterostome, characteristic of Echinodermata and Chordata. These phyla differ from protostomes in their embryonic development and share close evolutionary ties.
Step-by-step explanation:
An animal whose development is marked by radial cleavage and enterocoely is a deuterostome. This development pattern is characteristic of the phyla Echinodermata and Chordata, both of which belong to the superphylum Deuterostomia. The key distinction between deuterostomes and protostomes, such as mollusks, annelids, and arthropods, is the embryonic development sequence. In deuterostomes, the anus forms first and the mouth second, while in protostomes, it's the opposite.Echinoderms, including sea stars, brittle stars, sea urchins, sea cucumbers, and sea lilies, show radial symmetry and have a calcareous endoskeleton. The phylum Chordata includes animals with a notochord, such as vertebrates.
Both phyla display radial cleavage during embryonic development and develop their coeloms through a process called enterocoely, revealing their close evolutionary relationship.The animal whose development is marked by radial cleavage and enterocoely is echinoderm (c).Radial cleavage refers to a type of embryonic development where the cells divide symmetrically and form a radial pattern. Enterocoely refers to the formation of the body cavity from the outpouching of the archenteron (primitive gut tube) during development. These characteristics are unique to echinoderms, which include animals like sea stars, sea urchins, and sea cucumbers.Therefore, the correct answer is option c) Echinoderm.