Which Reaction Is the Correctly Balanced Half Reaction (In Acid $\rightarrow$

Which reaction is the correctly balanced half reaction (in acid solution) for the process below?
Cr₂O₇^2- (aq) $\rightarrow$ Cr³⁺ (aq)

A) 14 H⁺ + Cr₂O₇^2- + 6 e^- $\rightarrow$ 2 Cr³⁺ + 7 H₂O
B) 8 H⁺ + Cr₂O₇ + 3 e^- $\rightarrow$ 2Cr³⁺ + 4 H₂O
C) 8 H⁺ + Cr₂O₇ $\rightarrow$ 2 Cr³⁺ + 4 H₂O + 3 e^-
D) 12 H⁺ + Cr₂O₇^2- + 3 e^- $\rightarrow$ 2 Cr³⁺ + 6 H₂O