How Would the Kidneys Respond to Hypoventilation

How would the kidneys respond to hypoventilation?

A) increasing secretion of H⁺ and increasing production of new HCO₃^-
B) increasing secretion of H⁺ and decreasing reabsorption of HCO₃^-
C) decreasing secretion of H⁺ and increasing production of new HCO₃^-
D) decreasing secretion of H⁺ and decreasing reabsorption of HCO₃^-
E) increasing excretion of CO₂