"Pseudo" means false. Therefore, we can eliminate B from the choices since pseudocoelomates have a "false body cavity". Pseudocoelomates have a body cavity but it is not lined with mesodermal cells while coelomates have a body cavity lined with mesodermal cells. Therefore, the best answer is option C. the gut of a pseudocoelomate is surrounded by the body cavity, and the gut of a coelomate is surrounded by the mesoderm.
