A 38-year-old woman has been feeling lethargic for 4 months. On physical examination, she is afebrile, and her blood pressure is 140/90 mm Hg. Laboratory findings show the serum creatinine level is 5.8 mg/dL. C3 nephritic factor is present in serum, resulting in hypocomplementemia, and the ANA test result is negative. Urinalysis shows 2+ blood and 1+ protein. A renal biopsy is done; microscopic examination shows hypercellular glomeruli and prominent ribbonlike deposits along the lamina densa of the glomerular basement membrane. Which of the following forms of glomerulonephritis is most likely to be present in this patient?