Answer
Option a
Work Step by Step
Secretion of hydrogen ions into the kidney tubules makes the extracellular fluid less acidic.It is the body's mechanism to maintain the pH of the extracellular fluid.That is,when the pH of the extracellular fluid increases,tubular secretion of H+ ions also increases.The secreted H+ ions combine with phosphate or ammonia,which is then excreted via the urine.
