A. 0800, 1200, 1800, 2200: This schedule reflects four doses (q.i.d), not three, and includes administration during or after meals rather than before. “ac” (ante cibum) requires administration prior to meals to optimize absorption, especially for antibiotics like ampicillin. B. 0900, 1300, 1900: These times are after meals (postprandial), which can reduce absorption of ampicillin due to food interference in the gastrointestinal tract. This does not meet the “before meals” requirement and may decrease therapeutic effectiveness. C. 0700, 1100, 1700, 2100: This schedule again reflects four doses instead of three, making it inconsistent with “t.i.d.” Additionally, while some times are before meals, the extra dosing increases risk of toxicity and is not aligned with the prescription. D. 0700, 1100, 1600: This schedule provides three doses (t.i.d.) administered approximately one hour before meals at 0800, 1200, and 1700. Giving ampicillin on an empty stomach enhances absorption by minimizing competition with food, ensuring optimal serum drug concentrations.