Final answer:
The nurse's best response would be to encourage the patient to drink water and retest the urine pH in 3 hours.
Step-by-step explanation:
The nurse's best response to a urine pH of 6.8 from a patient's newly created ileal conduit would be to encourage the patient to drink at least 500 mL of water and retest in 3 hours (Option C).
This is because the pH of urine can vary from 4.5 to 8.0 and a pH of 6.8 falls within the normal range. Additionally, certain factors such as diet can influence urine pH, with citrus fruits, vegetables, and dairy products raising the pH. By encouraging the patient to drink water, the nurse helps ensure adequate hydration which may help maintain a normal pH range.