I think it's D. Sry if you get it wrong though
The whole body works together, as a “team.”If one of the parts of the body won’t work together as a team, everything will get messed up. The stomach muscles churn and mix the food with digestive juices that have acids and enzymes, breaking it into much smaller, digestible pieces. An acidic environment is needed for the digestion that takes place in the stomach.
Answer:
the answer, you can select it and write it down
Yes, as scientists could figure out what might have changed in the variables she used. Brainliest me and I can give you the whole system.