When discussing pharmacological considerations, a 68-year-old client asks, "Why do medications seem to act differently than they did when I was you. You base the response on what concept?

A. Over-the-counter (OTC) drugs have standardized dosages that are appropriate for all ages: OTC dosages are not always adjusted for age. Older adults may be more sensitive to drug effects and adverse reactions. B. Age-related changes affect the way drugs are metabolized by older adults: Aging affects liver and kidney function, body fat, and water composition, all of which influence drug absorption, distribution, metabolism, and excretion. C. Older adults may need larger doses of medication to bring about the desired effects: Often, smaller doses are required due to decreased clearance and increased sensitivity to drugs. D. Adverse drug reactions occur with similar frequency in older adults as the general population: Older adults are more prone to adverse drug reactions due to polypharmacy and physiological changes.