Final answer:
The shedding of renal tubular epithelial cells into the urine occurs in the largest numbers in the condition known as acute glomerulonephritis, which involves inflammation of the kidney's glomeruli. Therefore, the correct option is B.
Step-by-step explanation:
Renal tubular epithelial cells are shed into the urine in the largest numbers in the condition of acute glomerulonephritis. Acute glomerulonephritis is a disease that attacks the tiny filters in the kidneys, the glomeruli, leading to inflammation. This condition can result from various causes such as infections, immune system disorders, and diseases that induce inflammation. The shedding of epithelial cells into the urine reflects the degree of tubular damage that accompanies the primary glomerular injury.