A diagram in the course handout shows that a segment of an earthworm contains a coiled excretory tubule opening to the outside. Identify the related structure or process.

Metanephridia are excretory organs in many annelids. They remove wastes from coelomic fluid and help regulate water and salt balance. This MCQ belongs to the Annelida topic in Animal Diversity-I and is written to test concept understanding rather than memorized wording.