You are answering a USMLE-style medical question. Question: Two weeks after undergoing an emergency cardiac catherization with stenting for unstable angina pectoris, a 61-year-old man has decreased urinary output and malaise. He has type 2 diabetes mellitus and osteoarthritis of the hips. Prior to admission, his medications were insulin and naproxen. He was also started on aspirin, clopidogrel, and metoprolol after the coronary intervention. His temperature is 38°C (100.4°F), pulse is 93/min, and blood pressure is 125/85 mm Hg. Examination shows mottled, reticulated purplish discoloration of the feet. Laboratory studies show: Hemoglobin count 14 g/dL Leukocyte count 16,400/mm3 Segmented neutrophils 56% Eosinophils 11% Lymphocytes 31% Monocytes 2% Platelet count 260,000/mm3 Erythrocyte sedimentation rate 68 mm/h Serum Urea nitrogen 25 mg/dL Creatinine 4.2 mg/dL Renal biopsy shows intravascular spindle-shaped vacuoles. Which of the following is the most likely cause of this patient's symptoms?" Options: A) Renal papillary necrosis B) Cholesterol embolization C) Eosinophilic granulomatosis with polyangiitis D) Polyarteritis nodosa Reply with ONLY the letter of the correct answer (A, B, C, or D). No explanation.