You are answering a USMLE-style medical question. Question: A 58-year-old woman comes to the physician because of a 3-month history of left knee pain as well as stiffness upon waking for about 10–15 minutes. The pain is worse after standing a lot at work and when she climbs stairs. There is no history of trauma. She has hypercholesterolemia and hypertension. Her mother died of metastatic breast cancer 15 years ago, at the age of 65 years. She does not smoke or drink alcohol. Current medications include atorvastatin, labetalol, and aspirin. Over the past 2 months, she has been taking over-the-counter ibuprofen as needed for the joint pain. She is 163 cm (5 ft 4 in) tall and weighs 84 kg (185 lb); BMI is 31.8 kg/m2. Her temperature is 37°C (98.6°F), pulse is 88/min, and blood pressure is 114/68 mm Hg. Examination of the left knee shows tenderness on palpation of the anteromedial joint line; there is crepitus and pain with full flexion and extension. Serum uric acid concentration is 8.0 mg/dL and erythrocyte sedimentation rate is 15 mm/h. Which of the following is the most likely finding on imaging of the left knee? Options: A) Osteophytes with joint-space narrowing on x-ray B) Diffuse lytic-sclerotic bone lesions on x-ray C) Joint effusion and pannus on ultrasound D) Fluid-filled pouch on ultrasound Reply with ONLY the letter of the correct answer (A, B, C, or D). No explanation.