Answer: Ctenophora.
- A Cnidaria
- B Ctenophora
- C Porifera
- D Echinodermata
Correct answer: B. Ctenophora
Explanation: Pleurobrachia is a comb jelly belonging to phylum Ctenophora, exclusively marine animals that move using comb plates and show bioluminescence.
Moving across the animal phyla, body organisation becomes progressively more complex: from no symmetry and cellular organisation (Porifera) through radial/diploblastic (Cnidaria), bilateral/acoelomate (Platyhelminthes), pseudocoelomate (Nematoda), to a true coelom with full organ systems (Annelida and beyond).
Concept context
Phylum-level classification of the animal kingdom from Porifera to Chordata, based on body symmetry, coelom, and segmentation. One of the most example-heavy chapters for NEET.