Answer:
In order to best monitor the client's rehydration status, the nurse would assess the client's vital signs, including blood pressure, heart rate, respiratory rate, and temperature. The nurse would also monitor the client's intake and output, including urine output, and check for signs of dehydration, such as dry mucous membranes, poor skin turgor, and sunken eyes. Additionally, the nurse would monitor the client's electrolyte levels, including sodium and potassium, and administer fluids, electrolytes, and medications as needed to correct imbalances.