The correct option is C peristalsis
The process that is involved with the movement of food in the oesophagus is called peristalsis. After the food is broken down into smaller particles by the teeth and mixed with saliva, it passes on from the buccal cavity to the pharynx. From the pharynx, it passes on to the oesophagus. The process of peristalsis begins at the oesophagus. Peristalsis is a series of strong wave-like movements that carries the food from the oesophagus to the stomach.
Digestion is the process of breaking down food molecules into smaller components.
Absorption is the process by which the products of digestion are absorbed by the blood in order to be supplied to the rest of the body.
Defecation is the process by which the undigested wastes are eliminated from the body.