What is the main role of the small intestine?

The small intestine plays a crucial role in the digestive system, primarily responsible for the absorption of essential nutrients from food. After the stomach breaks down food into a semi-liquid form, it passes into the small intestine, where the majority of digestion and nutrient absorption occurs. The small intestine’s lining contains millions of tiny, finger-like structures called villi, which increase its surface area and facilitate the absorption of nutrients such as carbohydrates, proteins, fats, vitamins, and minerals into the bloodstream. This process is vital for maintaining the body’s energy levels and overall health, providing the necessary building blocks for growth, repair, and various bodily functions.

While the other options mention functions such as hormone production, bile storage, and waste formation, these activities do not capture the primary role of the small intestine, which is centered around nutrient absorption.