Which factors affect the gastrointestinal absorption of medicines? (Select all that apply.) Select 4 options. (Select All that Apply.).

Choice A rationale: The blood flow of the mucous lining of the stomach and intestines can affect how quickly a drug is absorbed. Choice B rationale: Drug distribution refers to how a drug spreads throughout the body, not its absorption in the gastrointestinal tract. Choice C rationale: Enzyme activity can affect how a drug is metabolized and absorbed. Choice D rationale: Gastric pH can affect drug absorption as some drugs are better absorbed in an acidic environment, while others are better absorbed in an alkaline environment. Choice E rationale: Gastric emptying time can affect drug absorption. Drugs may stay in contact with the absorptive tissue longer if the gastric emptying time is slower, allowing for increased absorption.