The definition of hygiene says cleanliness. A does not have to do with that. B does because keeping that clean prevents food diseases like salmonella. C has nothing to do with hygiene. D has nothing to do with being clean. So the answer would be B. I hope this helps!
B. Red blood cells contain a protein that binds with oxygen.
In you salivary glands there is an enzyme in the saliva that begins to break down the starches of the food.
