Answer:
The correct answer is the third statement.
Step-by-step explanation:
To hold the bodies together, to keep them incline, and to permit for movement, all the animals require support structures. There are three kinds of support systems found in animals, that is, exoskeleton, hydrostatic skeleton, and the endoskeleton. Of the mentioned support systems, the hydrostatic skeleton is used by worms for movement.
In the worms, a fluid-filled cavity known as coelom, and the fluid known as coelomic fluid is found between the muscles and the digestive tract. This coelomic fluid works as a hydrostatic skeleton. In worms, movement takes place by contraction of muscles that compress the coelomic fluid, that is, the watery body fluid resulting in the change in body composition.