Correct Answer: D
Explanation:
Figure 2 illustrates the three basic body plans encountered in the bilateria: the acoelomates (e.g., flatworms, flukes, and tapeworms), the pseudocoelomates (e.g., roundworms, pinworms, hookworms and rotifers), and the coelomates (e.g., snails, clams, octopuses, earthworms, and leeches). Recall that pseudocoelomates differ from coelomates in that their body cavities are not completely lined by mesoderm-derived tissue, but instead have mesoderm only on one side, with endoderm on the other