The concentration of protein in the blood is higher in post-glomerular blood than in arterial blood because

A)protein is digested and then concentrated in glomerular (Bowman's)capsule.
B)the kidney manufactures and then stores protein in the glomerulus.
C)reabsorption of protein occurs.
D)water passes into the capsule,but protein molecules are too large to move into the capsule and are concentrated in the blood.
E)water concentration increases and protein concentrations decrease.