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Recent exercise and acute posture changes cause short-term shifts in plasma volume and distribution of analytes (e.g., hemoconcentration of proteins, calcium, and hematocrit; transient changes in lactate and potassium). Best practice is to standardize patient posture and activity by having the patient sit or recline quietly for approximately 15 minutes prior to collection. Option C reduces variability and aligns the draw with reference conditions used to establish decision limits. Drawing immediately (Option A) risks spurious results and potential recollection. Water (Option B) may aid hydration but does not normalize post-exercise hemodynamics in two minutes. Continued pacing (Option D) perpetuates physiologic flux. The phlebotomist should document significant deviations (e.g., non-fasting, recent strenuous activity) when unavoidable and communicate with the care team if timing constraints exist (e.g., STAT orders). Standardizing pre-draw conditions is a core competency because preanalytical factors often exceed analytical variability and directly affect result interpretation.