Which of the following medications is indicated for the prevention of thromboembolism?

Warfarin is indicated for the prevention of thromboembolism because it is an anticoagulant that works by inhibiting vitamin K-dependent clotting factors, which helps to reduce the ability of the blood to form clots. This action makes it effective in preventing thromboembolic events, such as deep vein thrombosis (DVT) or pulmonary embolism, especially in patients with conditions like atrial fibrillation or those who have undergone certain surgeries that increase their risk of clot formation. By maintaining the blood's fluidity, Warfarin helps prevent the formation of dangerous blood clots that can lead to serious complications.

The other medications listed serve different purposes: Latanoprost is used to treat glaucoma by reducing intraocular pressure, Metformin is primarily used for managing type 2 diabetes through the regulation of glucose, and Simvastatin is a statin used to lower cholesterol levels. None of these have a role in preventing thromboembolism as effectively as Warfarin.