The correct answer is D. Acoelomates.
Acoelomates are animals that lack a true body cavity. Their organs are located directly between the body wall and the digestive tract. Acoelomates are a diverse group of animals, including flatworms, rotifers, and nematodes.
Coelomates are animals that have a true body cavity, which is a fluid-filled space that separates the digestive tract from the body wall. Coelomates are more complex than acoelomates, and they include most of the familiar animals, such as insects, worms, and vertebrates.
Pseudocoelomates are animals that have a pseudocoelom, which is a body cavity that is not lined with mesoderm. Pseudocoelomates are less complex than coelomates, and they include roundworms and some other worms.
Wild is not a correct answer to the question. It is not a term used to describe animals.