Saliva to break down food chemically by using enzymes. which statement best describes this process? a) saliva mixes the food particles. b) saliva produces gas from the food. c) saliva moves food through the digestive track. d) saliva changes the chemical composition of food.

Answer is D) Saliva changes the chemical composition of food

A enzyme is a catalyst for chemical reactions, meaning it either facilitates or initiates a chemical reaction. In this case, saliva uses enzymes to change the chemical composition of food into compounds that our body can easily process and turn into energy. 

Before it is yellow brown and after if its done  right yellow.