Problem: A 78-year-old man is evaluated for bilateral calf pain. He notes that the pain is worse after ambulation and improves with rest. He denies lower extremity erythema. Medical history is notable for type 2 diabetes mellitus and tobacco use disorder. Current medications include metformin and glipizide. On physical examination, the vital signs include blood pressure of 148/82 mm Hg. On the plantar surface of the left foot, there is a well-circumscribed, non-healing ulcer that measures 1 x 1cm. Ankle-brachial index is measured as 1.50. Which of the following is the most accurate interpretation of these results? A. Occlusive arterial disease B. Multilevel occlusive arterial disease C. Normal D. Noncompressible arteries