A 64-year-old woman with type 2 diabetes for 10 years now develops increasing fatigue, dyspnea, and pedal edema. On examination, her blood pressure is 165/90 mmHg, pulse 90/min, JVP is 4 cm, heart sounds are normal, lungs are clear, and there is 3+ pedal edema.Her urinalysis is positive for 3 gm/L of protein and no casts or red blood cells. An abdominal ultrasound reveals normal size kidneys and no hydronephrosis. Which of the following renal diseases is the most likely diagnosis in this patient?