What is the type of symmetry found in adult echinoderms?

Step-by-step solution

These animals have an endoskeleton of calcareous ossicles and, hence, the name Echinodermata (Spiny bodied, All are marine with organ-system level of organisation.They are triploblastic and coelomate animals. Digestive system is complete with mouth on the lower (ventral) side and anus on the upper (dorsal) side. An excretory system is absent. Sexes are separate. Reproduction is sexual. Fertilisation is usually external. Development is indirect with free-swimming larva.The most distinctive feature of echinoderms is