DCT helps in
(A) Conditional reabsorption of Na⁺  and water
(B) ${\mathrm{HCO}}_3^{-}$ absorption 
(C)  pH maintenance 
(D) Selective secretion of ${\mathrm{H}}^{+} \mathrm{and} {\mathrm{K}}^{+}$

Distal Convoluted Tubule (DCT) helps in conditional reabsorption of Na⁺ and water. DCT is also capable of reabsorption of HCO₃ ^– and selective secretion of hydrogen and potassium ions and NH₃ to maintain the pH and sodium-potassium balance in blood.