Final answer:
Organisms in the phylum Mollusca do not possess tube feet; instead, they have a muscular foot used for locomotion and a mantle that may secrete a shell and forms a mantle cavity for respiration.
Step-by-step explanation:
Organisms in the phylum Mollusca do not possess tube feet. Tube feet are rather a characteristic of echinoderms, such as starfish, which is another phylum entirely. Mollusks instead have a variety of other anatomical features. For example, they often have a muscular foot used for locomotion or anchorage, and a mantle, which can secrete a protective shell and cover the body forming a mantle cavity. The mantle cavity in aquatic mollusks facilitates respiration through gills, known as ctenidia.
Thus, the statement that Mollusca possess tube feet is false (option b).