In a specimen-based viva, the examiner describes this case: a segmented soil animal improves soil aeration and has few setae but no parapodia. Choose the concept that fits it best.

Earthworms are oligochaete annelids. They have relatively few setae per segment and lack parapodia, making them different from polychaetes such as Nereis. This MCQ belongs to the Oligochaeta topic in Animal Diversity-I and is written to test concept understanding rather than memorized wording.