Final answer:
The major site for nutrient absorption in the digestive system is the small intestine.
Step-by-step explanation:
The major site for nutrient absorption is the small intestine. The small intestine is a long tube-like organ that completes the digestion of protein, fats, and carbohydrates. It is covered with finger-like projections called villi, which increase the surface area of the intestine and enhance the absorption efficiency of nutrients.
The majority of nutrient molecules, about 95 percent, are absorbed in the small intestine, particularly in the second part called the jejunum.