This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Blood Vessels, Subject name: Pathology
[{'content': 'A 61-year-old man presents with a 5-year history of pain in both legs during exercise. He has been treated for diabetes for 8 years. His fasting blood glucose is 280 mg/dL. Which of the following best explains the pathogenesis of leg pain in this patient? \nSelect and explain. \nA. Atherosclerosis, B. Malignant hypertension, C. Microaneurysms, D. Peripheral neuropathy', 'role': 'user'}, {'content': 'Answer: A \nExplanation: The extent and severity of atherosclerotic lesions in medium-sized and large arteries are increased in patients with long-standing diabetes. Leg pain during walking or exercise, which forces the patient to stop or limp (intermittent claudication) is typically a complication of atherosclerosis involving the major arteries of the lower extremities. Peripheral neuropathy (choice D) is a complication of diabetes but is an unlikely cause of claudication. Diabetes does not cause vasculitis (choice E).Diagnosis: Atherosclerosis', 'role': 'assistant'}]