∙ Absorption is the movement of digested food molecules through the wall of the intestine into the blood or lymph .
∙ Ingestion is the intake of food via buccal cavity
∙ Egestion is the elimination of undigested and unabsorbed food from the body.
∙ Assimilation is the absorption of vital nutrients by the body.It is the process of absorption of vitamins, minerals, and other chemicals from food as part of the nutrition of an organism.
So,the correct answer is
Ingestion - Intake of food via buccal cavity
Absorption - Obtaining energy from the absorbed nutrient
Assimilation - Absorption of vital nutrients by the body
Egestion - Elimination of undigested and unabsorbed food from the body