Concept:A snail belongs to the group of molluscs whose body is not separated into a thorax or abdomen, but into three main regions.
Explanation:The three main regions of a snail's body are the head, the visceral mass, and the foot.
The head is the front part that carries tentacles and simple eyes.
The visceral mass is a soft hump that holds the main internal organs like the digestive and reproductive systems.
The foot is a flat, muscular structure used by the snail for creeping or crawling.
These are the only major divisions of a snail's body, so options that mention thorax or abdomen are not correct for a snail.
Thus, the body of a snail is divided into head, visceral mass, and foot.
This matches option D.
Answer:D. visceral mass and foot