Answer: (4)Jellyfish
Jellyfish belong to the phylum Coelenterata; and thus is not triploblastic.
Triploblastic
The group of Annelids has many worms. Their bodies are segmented and consist of 3 layers and hence called as Triploblastic animals. Triploblastic refers to having 3 layers as inner skin, middle skin and outer skin.
Examples:
Earthworm, Sand worm, and Leech.
