A nurse is caring for a 4-year-old child who has dehydration. Which of the following findings should the nurse identify as the priority?

A. Sodium 142 mEq/L: This is within the normal range for sodium (135–145 mEq/L) and does not indicate an immediate threat. B. Potassium 2.5 mEq/L: This is critically low (normal range is 3.5–5.0 mEq/L), and hypokalemia can cause life-threatening cardiac arrhythmias. C. Urine specific gravity 1.025: Although elevated, it is not as critical as severe hypokalemia. D. Blood glucose 110 mg/dL: This is a normal glucose level and not a priority.