Answer:
Peristalsis is also part of mechanical digestion. This refers to involuntary contractions and relaxations of the muscles of your esophagus, stomach, and intestines to break down food and move it through your digestive system.
Explanation:
Because they had high blood pressure
The correct answer is C.
An author's credentials can determine a health source's credibility. None of the other options would apply to credibility. When it comes to health, if you want to make sure that what you are researching or reading is authentic and reliable you need to find out whether the author is a professional health expert or not. You can do this by finding out their credentials.