The correct option is B.
The alimentary canal is the pathway through which ingested foods move from the mouth all through into the anus. At each portion of the canal, different types of chemical reactions take place, which digest the eaten food and prepare the useful part for absorption and the waste part for excretion. In the alimentary canal, the stomach open into the small intestines. The small intestines is the site where the useful part of the nutrients will be absorbed into the system through villi.