Which of the Following Is the Equilibrium Constant Expression for the Reaction

Which of the following is the equilibrium constant expression for the reaction? 2NO(g) + O₂(g) ? 2NO₂(g)

A) K_eq = $\frac{\left[\mathrm{NO}_{2}\right]}{\left[\mathrm{NO}^{2}\left[\mathrm{O}_{2}\right]\right.}$
B) K_eq = $\frac { \left[ \mathrm { NO } _ { 2 } \right] ^ { 2 } } { \left[ \mathrm { NO } ^ { 2 } \left[ \mathrm { O } _ { 2 } \right] \right. }$
C) K_eq = $\frac { \left[ \mathrm { NO } _ { 2 } \right] ^ { 2 } } { [ \mathrm { NO } ] ^ { 2 } + \left[ \mathrm { O } _ { 2 } \right] }$
D) K_eq = $\frac { 2 \left[ \mathrm { NO } _ { 2 } \right] } { 2 [ \mathrm { NO } ] + \left[ \mathrm { O } _ { 2 } \right] }$
E) None of the choices are correct.