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The answer is True. A drug has different stages in its lifespan in the body. They include Absorption, Distribution, Metabolism, and Excretion. The route of the drug that affects its absorption includes oral, topical, intravenous, and etcetera. Type of drugs also affects absorption because, for example, strongly ionized drugs cannot easily cross membranes. Absorption for topical drugs on obese people is also reduced compared to normal weight people.
This actually depends on which level of education you are and what they are looking for. Most people though merely considers it a part of the Digestive System as the bile it stores is used during digestion.
I have seen however several people put it down as part of the bilary system or subsystem which responsible for the creation and distribution of bile.