Hint: The organ that absorbs food nutrients through villi lies between the stomach and the large intestine, and receives bile and pancreatic juice through the pancreatic duct, which helps to improve digestion.
Small intestine absorbs food nutrients through villi. The small intestine which is also known as the small bowel is an organ within the alimentary canal, in which most of the end absorption of minerals and nutrients from food takes place. The villi further helps to increase the surface area of the intestine, so that more digested food absorption can take place.
The small intestine is further divided into three distinct regions – the duodenum, jejunum, and ileum. The duodenum is known to be the shortest, where preparation for absorption with the help of small finger-like projections called villi begins. The jejunum is the part that is specialized for the absorption through its lining by enterocytes: small nutrient particles that are previously digested by enzymes within the duodenum. The important function of the ileum is to soak up vitamin B12, bile salts, and also many other products of digestion that weren't absorbed by the jejunum. The length of the small intestine will vary greatly. It can be as short as 3.00 m to as long as 10.49 m. It will also depend on the measuring technique used. The standard length in a living person is 3m–5m. The length depends both on how tall the person is and the way the length is measured. Taller people generally have an extended small intestine and measurements are generally longer after death and when the bowel is empty
So, the correct answer is ‘Small intestine’.
Note: The small intestine will also support the body's immune system. The presence of gut flora in it appears to contribute positively to the host's immune system. Peyer's patches, located within the ileum of the small intestine, are a crucial part of the digestive tract's local immune system.