A nurse in a clinic is caring for a client who has recently begun taking warfarin. The nurse is reviewing potential drug and food interaction risks and should instruct the client to avoid which of the following?

Choice A rationale: White beans contain relatively low amounts of vitamin K. They do not significantly interfere with the mechanism of action of warfarin or the maintenance of a stable International Normalized Ratio. Choice B rationale: Cantaloupe is a fruit that is high in potassium and vitamin C but very low in vitamin K. It does not pose a risk for interaction with anticoagulant therapy. Choice C rationale: While green beans are a vegetable, their vitamin K content is significantly lower than that of leafy greens. They generally do not require strict avoidance for patients on warfarin. Choice D rationale: Spinach is exceptionally high in vitamin K, which directly antagonizes the effects of warfarin by promoting the synthesis of clotting factors. Inconsistent intake can lead to subtherapeutic INR levels.