A 65-year-old man with a 40 pack-year smoking history and hyperlipidemia presents to the emergency department with a second episode of painless right monocular vision loss that resolved spontaneously within 90 minutes. He reports an identical episode 2 months ago that also resolved completely. Current vital signs include BP 158/92 mmHg, HR 88 bpm, RR 16, temperature 37.0°C, and SpO2 98% on room air. On neurologic examination, he has normal visual acuity and normal fundoscopic examination bilaterally. There are no other focal neurologic deficits. Noncontrast head CT is unremarkable. Carotid duplex ultrasound demonstrates 70% stenosis of the right internal carotid artery with normal findings on the left. Brain MRI shows no acute or chronic infarction. The patient is currently taking aspirin 81 mg daily. Which of the following is the most appropriate next step in management?

1. A)Initiate dual antiplatelet therapy with clopidogrel and continue aspirin, then reassess carotid imaging in 3 months
2. B)Start warfarin with a target INR of 2-3 to prevent acute thrombotic events
3. C)Refer for carotid endarterectomy after optimization of medical therapy including blood pressure control and statin therapyGABARITO
4. D)Perform urgent carotid angiography with percutaneous transluminal angioplasty and stent placement
5. E)Increase aspirin to 325 mg three times daily and add high-dose atorvastatin; repeat carotid duplex in 6 months