What is a contraindication for the use of warfarin?

A. Chronic kidney disease: While kidney disease requires careful monitoring of anticoagulants, it is not an absolute contraindication for warfarin. Dose adjustments and frequent INR monitoring can allow safe use in many patients with renal impairment. B. Hypertension: Hypertension is common in patients taking warfarin but is not a contraindication. Careful blood pressure control is important to reduce the risk of hemorrhagic complications, but warfarin can still be used safely. C. Diabetes mellitus: Diabetes does not preclude warfarin therapy. Patients with diabetes may require monitoring for cardiovascular risk, but anticoagulation is not contraindicated solely due to diabetes. D. Active bleeding disorders: Warfarin inhibits clotting and increases bleeding risk, making it contraindicated in patients with active bleeding. Administering warfarin in this context could lead to life-threatening hemorrhage and must be avoided.