Start with the Skeleton Half-Reaction NO₃ ^- →NO₂

Start with the skeleton half-reaction NO₃ ^- →NO₂. When balanced in acid solution, what other species appear on the left side of the equation, in addition to NO₃ ^-?

A) H₂O + 2 e ^-
B) 2 H⁺ + e ^-
C) H⁺ + 2 e ^-
D) 2 H⁺
E) none of these