A buffer is prepared with $Na{H}_{2}P{O}_4$ and $N{a}_{2}HP{O}_4.$ What is the correct net ionic equation describing what happens when a small amount of NaOH is added to the buffer?

$H_{3}P{O}_4(aq)+O{H}^{-}(aq)H_{2}P{O}_4^{-}(aq)+H_{2}O(l)$

$H_{2}P{O}_4^{-}(aq)+H_3{O}^{+}(aq)H_{3}P{O}_4(aq)+H_{2}O(l)$

$H_{2}P{O}_4^{-}(aq)+H_{2}O(l)H_{3}P{O}_4(aq)+H_3{O}^{+}(aq)$