To which phylum does earthworm belong?

 

The earthworm belongs to the phylum Annelida.

Explanation:
The phylum Annelida includes animals that have a segmented body structure, meaning their bodies are divided into many small rings or segments. Earthworms show this segmentation clearly, with a soft, long, and cylindrical body divided into repeating segments.

They are bilaterally symmetrical, meaning their left and right sides are mirror images. Earthworms are also cold-blooded (ectothermic), have a coelom (body cavity), and lack any bones (they are invertebrates).

Phylum Annelida is also known for other animals like leeches and marine worms. Earthworms play an important role in nature by improving soil fertility through burrowing and decomposition.