Which of the following is NOT a function of the digestive system?

The digestive system has several critical functions, including breaking down food, absorbing nutrients, and eliminating waste. However, producing hormones is primarily the function of the endocrine system rather than the digestive system. While it's true that certain hormones related to digestion are produced by the digestive organs (such as the pancreas and stomach), the act of producing hormones itself is not a primary function of the digestive system as a whole. Therefore, identifying the production of hormones as not being a direct function of the digestive system highlights a key distinction between these two systems and underscores the specific roles each plays in maintaining bodily function.