The correct option is A coelomic fluid
Unlike humans, earthworms have no skeleton. Instead, their coelom is filled with a milkish fluid called coelomic fluid. This fluid makes the body segments turgid (hydroskeleton) and helps in locomotion.
Clitellum is the prominent dark band of glandular tissue in the 14th to 16th segments of the earthworm. It secretes the cocoon.
Setae are chitinous structures that help in locomotion. It is S shaped and found in each body segment (except the first, last and clitellar segments).
The external and internal segments in the body of the earthworm are known as metameres. This type of segmentation is called metameric segmentation.