Which of the following groups of animals is bilaterally symmetrical and triploblastic?
Aschelminthes (roundworms)
Ctenophores
Sponges
Cnidarians
Bilateral symmetrical: Such animals can be divided into two equal halves along any one plane, that is, either transversely or longitudinally. For example, Aschelminthes, annelids, arthropods, and vertebrates
Triploblastic animals: Such animals develop three germ layers as innermost endoderm, middle mesoderm and outer ectoderm, for example, aschelminthes.
Hence,
Aschelminthes are bilaterally symmetrical, triploblastic and pseudocoelomate.