The primary purpose of anticoagulants like Warfarin is to:

The primary purpose of anticoagulants such as Warfarin is to prevent blood clots from forming. Warfarin works by inhibiting the synthesis of vitamin K-dependent clotting factors in the liver, which are essential for the coagulation cascade that leads to clot formation. By decreasing the levels of these factors, Warfarin effectively reduces the ability of the blood to clot, thereby helping to prevent conditions such as deep vein thrombosis (DVT), pulmonary embolism, and stroke in individuals who are at risk for these complications.

Other options do not accurately reflect the role of anticoagulants. For instance, reducing blood flow to the heart is not a function of anticoagulants; rather, it relates more to medications that affect heart function or circulation. Increasing red blood cell production pertains to erythropoiesis, which is more closely associated with medications like erythropoietin rather than anticoagulants. Lowering blood sugar levels is relevant to medications used for diabetes management and has no connection to the action of anticoagulants. Thus, the focus on preventing the formation of blood clots underscores the correct answer's significance and relevance in clinical practice.