Answer:
Option-D
Step-by-step explanation:
The small intestine is the part of the digestive system which is very long in its length but small in diameter. The small intestine begins after the stomach and the main parts of the intestine are duodenum, jejunum and ileum.
The small intestine is the main site for the digestion of chyme and absorption of the nutrients from the digested material. The food enters into the small intestine from the stomach in which the digestion of proteins begins.
In the stomach, the enzyme pepsin acts on the peptide bonds of the protein and break it down into the smaller proteins. Therefore, the food that enters the small intestine has already been broken down into smaller proteins.
Thus, Option-D is correct.