Which of the following organisms belongs to Coelenterata (Cnidria) ?

Phylum Coelenterata (also known as Cnidaria) consists of aquatic, mostly marine animals characterized by stinging cells called cnidoblasts and a central gastro-vascular cavity [4]. Hydra and sea anemone (Adamsia) are classic examples of this phylum, exhibiting the polyp body form [5]. Other options belong to different phyla: Planaria and liverfluke are flatworms belonging to Platyhelminthes [3]. Sea urchins and sea cucumbers are marine animals with spines or arms belonging to Echinodermata [1]. Euplectella (Venus’s flower basket) and Sycon are sponges belonging to Phylum Porifera, characterized by a cellular level of organization and a canal system for water circulation [3]. Cnidarians like Hydra are simple multicellular organisms that can reproduce asexually through budding [3].

Sources

1. [3] Science ,Class VIII . NCERT(Revised ed 2025) > Chapter 13: Our Home: Earth, a Unique Life Sustaining Planet > Ever heard of ... Ever heard of ... > p. 221
2. [4] https://ncert.nic.in/textbook/pdf/kebo104.pdf
3. [5] https://www.sciencedirect.com/topics/earth-and-planetary-sciences/coelenterate
4. [1] Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 9: Indian Biodiversity Diverse Landscape > Echinoderms > p. 155