Explanation:

- Annelida:

- Correct Answer: The body wall of Annelids is indeed composed of both circular and longitudinal muscle fibers. It is covered with a moist cuticle secreted by an epithelial epidermis. This lets them move efficiently in their environment.

- Arthropoda:

- Arthropods have an exoskeleton made of chitin, not a cuticle with muscle fibers. Their muscles attach to the inside of the exoskeleton and are not circular and longitudinal like in Annelids.

- Platyhelminthes:

- These flatworms have a simple body structure with a ciliated epidermis. Their muscle fibers are largely lacking the complexity found in Annelids and don't have the same type of cuticle.

- Coelenterata:

- Also known as Cnidarians, these animals, such as jellyfish, have a simpler body structure mainly comprising a single layer of cells and lack the muscular composition and cuticle of Annelids.