An individual is constipated. They take magnesium salts to help loosen the stool. Why does this work? A. Water moves from the intestines to the blood because the blood is hypertonic B. Water moves from the intestines to the blood because the blood is hvpotonic. C. Water moves from the blood to the intestines because the blood is hvpertonic D. Water moves from the blood to the intestines because the blood is hypotonic.