Pseudocoelom is a characteristic feature of which of the following?

Explanation

The pseudocoelom is a characteristic body cavity found in animals belonging to the phylum Aschelminthes, also known as Nemathelminthes. This cavity lies between the body wall and the digestive tract, but unlike a true coelom, it is not fully lined by mesodermal tissue. Instead, the outer side of the pseudocoelom is lined by mesoderm, while the inner side is lined by endoderm. This structural arrangement makes the pseudocoelom function as a hydrostatic skeleton, helping the animal maintain body shape and allowing efficient movement by providing resistance for muscle contraction. It also serves as a space for the distribution of nutrients, removal of metabolic wastes, and temporary storage of reproductive products. Because of its simplicity and functional importance, the pseudocoelom is considered a key evolutionary advancement in Aschelminthes, enabling them to survive in a wide range of environments.