The majority of the digestion processes take place in the

Mouth Small intestineLarge intestineStomach

Explanation.

Chemical processes that contribute to digestion begin in the mouth with action of saliva on food. However, most of the chemical digestive processes occur in the stomach and small intestine – where the partly-digested materials are subjected to gastric juices, pancreatic juice, succus entericus and so on. To be slightly more detailed, most digestion takes place in the duodenum section of the small intestine.