Final answer:
The treatment of ischemic stroke when tPA is not an option is Aspirin, which helps to prevent clots from becoming larger and causing further issues.
Step-by-step explanation:
The treatment of ischemic stroke when tissue plasminogen activator (tPA) is not an option includes anti-platelet and antithrombotic medications. The correct answer is A) Aspirin, which is often prescribed to prevent the clots from becoming larger and reducing the risk of a first or recurrent stroke. Aspirin may sometimes be combined with another antiplatelet drug, like clopidogrel, in a dual antiplatelet therapy (DAPT), which is generally used in patients with a high risk of cardiovascular events, though this combination is not the standard initial treatment for acute ischemic stroke. Warfarin is an anticoagulant which is not typically used in the immediate treatment of acute ischemic stroke, and similarly, clopidogrel alone is not the standard first-line treatment for patients who cannot receive tPA. Instead, aspirin is typically used because of its ability to prevent the enlargement of existing clots, potentially averting more serious problems.