In response to metabolic acidosis,the kidneys increase the excretion of net acid.Which of the following is the most important component of this compensatory response?
A)Increased filtered load of HCO3− B)Enhanced reabsorption of HCO3− by the proximal tubule C)Increased synthesis and excretion of NH4+ D)Reduced H+ secretion by the distal tubule and collecting duct E)Reduced secretion of HCO3− by the collecting duct