A nurse is providing teaching to a client who has a new prescription for warfarin. Which of the following instructions should the nurse include in the teaching?

Rationale: A. "This medication can cause back pain.": Back pain is not a common or expected adverse effect of warfarin. Teaching should focus on bleeding risks and precautions rather than unrelated symptoms. B. "Avoid taking this medication with milk products.": Milk does not significantly affect warfarin absorption. The main dietary consideration is maintaining consistent vitamin K intake, as large fluctuations can alter anticoagulation. C. "Use an electric razor when shaving while taking this medication.": Warfarin increases the risk of bleeding and bruising. Using an electric razor reduces the chance of cuts, promoting safety during routine grooming. D. "Avoid prolonged exposure to sunlight while taking this medication.": Sun exposure is not contraindicated with warfarin; there is no significant interaction between warfarin and UV light.