In order to digest food, the human body requires a. high activity to burn off energy. b. physical reactions in the stomach lining. c. sleep to perform the necessary break down of molecules in food. d. enzyme catalysts to speed up reactions.

D. enzyme catalysts to speed up reactions

Explanation:

In order to digest food, the human body requires enzyme catalysts to speed up reactions. The digestion process starts from the mouth, to the stomach to the small intestines. In the mouth, we chew the food and mixes it with the saliva which contains salivary amylase. In the stomach, pepsin is the enzyme present. It digest proteins and nutrients from foods are sent to the different parts of the body that needs it.

D. Enzyme catalysts to speed up reactioins

Explanation:

just took the test :)

the answer to this question is 3.