You are answering a USMLE-style medical question. Question: A 67-year-old man comes to the physician for a routine medical check-up prior to a scheduled elective femoropopliteal bypass surgery of his left leg. He feels well but reports occasional episodes of weakness and numbness in his left hand. He has a history of peripheral arterial disease, type 2 diabetes mellitus, hypertension, hypercholesterolemia, and gout. The patient has smoked 1 pack of cigarettes daily for the past 50 years. He drinks 3 cans of beer daily. His current medications include aspirin, metformin, enalapril, simvastatin, and febuxostat. His temperature is 37.3°C (99.1°F), pulse is 86/min, and blood pressure is 122/76 mm Hg. The lungs are clear to auscultation. Cardiac examination shows no murmurs, rubs, or gallops. Auscultation of the right side of the neck shows a bruit. There is a right-sided reducible inguinal hernia. Neurological examination shows no abnormalities. A complete blood count and serum concentrations of electrolytes, creatinine, and glucose are within the reference ranges. An electrocardiogram shows signs of mild left ventricular hypertrophy. An x-ray of the chest shows no abnormalities. Which of the following is the most appropriate next step in management? Options: A) Ultrasonography of the neck B) Echocardiography C) Warfarin therapy D) CT angiography of the head Reply with ONLY the letter of the correct answer (A, B, C, or D). No explanation.