EVERYDAY SCIENCE

Detailed explanation-1: -Hence, the correct answer is ‘Annelida’

Detailed explanation-2: -Annelids have nephridia as an excretory organ. Thus, the correct answer here is (D) Annelids. In earthworm, the nephridia are generally grouped in pairs throughout the segment of the worm’s body.

Detailed explanation-3: -Nephridia occur in two forms. The simpler, more primitive protonephridia, found in flatworms, ribbon worms, and rotifers, are usually scattered among the other body cells. More advanced, segmented invertebrates, such as earthworms, possess the more complex metanephridia, usually arranged in pairs.

Detailed explanation-4: -The nephridium is a pair of invertebrate kidneys that operate similarly to vertebrate kidneys. In earthworms, nephridia are responsible for maintaining osmoregulation. In earthworms, there are three types of nephridia that are named based on their locations.