A 71-year-old man with a history of type 2 diabetes mellitus, hypertension, and prior myocardial infarction presents to the emergency department with sudden onset dysarthria and right facial droop. His wife reports he was last seen in his normal state of health 2 hours and 20 minutes ago. Vital signs are: blood pressure 158/92 mmHg, heart rate 78/min, respiratory rate 16/min, temperature 37.0°C. National Institutes of Health Stroke Scale (NIHSS) score is 6. Physical examination confirms acute right-sided facial weakness with mild speech difficulty. Noncontrast CT of the head shows no evidence of acute intracranial hemorrhage or other acute abnormality. Which of the following is the most appropriate next step in management?

1. A)Administer intravenous alteplase (tPA) at 0.9 mg/kg body weightGABARITO
2. B)Obtain CT perfusion imaging to assess the ischemic penumbra before making treatment decisions
3. C)Perform diffusion-weighted MRI to confirm acute ischemic stroke before thrombolytic therapy
4. D)Initiate aspirin 325 mg orally and schedule urgent carotid ultrasound to determine stroke etiology
5. E)Initiate continuous heparin infusion and arrange urgent neurosurgery consultation for mechanical thrombectomy