Which of the following statements describes the function of saliva?

Saliva plays a crucial role in the digestive process, primarily through its ability to initiate the breakdown of food. It contains enzymes, such as amylase, that begin the digestion of carbohydrates in the mouth. When food enters the mouth, the salivary glands secrete saliva to moisten the food, forming a bolus that is easier to swallow. The enzymatic activity in saliva is essential, as it starts to break down complex carbohydrates into simpler sugars even before the food reaches the stomach. This enzymatic action is a critical first step in digestion, highlighting the importance of saliva in the overall digestive process.

The other statements, while related to bodily functions, do not accurately describe the primary role of saliva. Saliva does not absorb nutrients into the bloodstream; nutrient absorption occurs primarily in the intestines. It is also not responsible for neutralizing stomach acid, as this is mainly the function of bicarbonate secreted by the pancreas. Furthermore, saliva has no role in facilitating gas exchange in the lungs, which is a function carried out by the respiratory system.