If those are the optional answers, it's most likely sodium.
Answer:enzymes
Explanation:during digestion, food is broken down by chewing in the mouth.enzymes also acts on foods to reduce them into simpler constituents.enzymes acts on food in the mouth, stomach, intestine etc.
Enzymes that acts on proteins helps to break the peptides bonds present in proteins.they break up the polypeptide chains into amino acids .An example is trypsin .the conditions necessary for these enzymes to acts may be specific.some require acidic environment while others require basic environment.pepsin for example requires stomach hydrochloric acid to be converted from it's inactive form, pepsinogen.
The resultant Amino acids are then absorbed in the small intestine
I think salt is it
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