Identify the mismatched pair regarding the source and action of Cholecystokinin.
Stomach that inhibits the release of pancreatic juice
Intestinal epithelial cells that stimulate the secretion of bile
Kidneys that regulate blood pressure
Hypothalamus controls hunger and satiety
Option 2, "Intestinal epithelial cells that stimulate the secretion of bile," is the mismatched pair. Cholecystokinin is indeed secreted by intestinal epithelial cells, but its main action is to stimulate the contraction of the gall bladder, leading to the release of bile into the digestive system. It does not directly stimulate the secretion of bile by the intestinal epithelial cells. Hence, the correct answer is option 2.