Answer: Nephridia.
- A Flame cells
- B Nephridia
- C Malpighian tubules
- D Green glands
Correct answer: B. Nephridia
Explanation: Earthworms (Annelida) have nephridia as excretory organs. Flame cells are found in flatworms, and Malpighian tubules in insects.
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.