In the Condition Diabetes Mellitus,why Does Glucose Appear in the Urine

In the condition diabetes mellitus,why does glucose appear in the urine? 

A) The plasma concentration of glucose becomes so high that it diffuses from peritubular capillaries into the proximal tubule,down its concentration gradient.
B) The filtered load of glucose becomes greater than the tubular maximum for its reabsorption.
C) Without the hormone insulin,glucose cannot enter proximal tubule epithelial cells.
D) The rate of tubular secretion of glucose becomes greater than the sum of glucose filtration and reabsorption.
E) Without insulin,the glomerular filtration barrier becomes extremely leaky to glucose,which is not normally filterable.