Patient Case: A 28-year-old woman with a known history of systemic lupus erythematosus presents with increasing lower extremity swelling and weight gain over the past month. Laboratory studies reveal a serum albumin of 2.0 g/dL and a 24-hour urine collection showing 4.5 grams of protein. A renal biopsy is performed. Question: Which of the following histopathological findings is most characteristic of membranous lupus nephritis?
