K_c for N₂+O₂ $\rightleftharpoons$ 2NO at certain temp is 1.6 x 10^-3, then K_p for NO $\rightleftharpoons$ $\frac{1}{2}$N₂ + $\frac{1}{2}$ O₂ at same temperature will be:

N₂ + O₂ ⇌ 2NO 

K_C=1.6 x 10^-3

${\mathrm{K}}_{\mathrm{c}}=\frac{{\left[\mathrm{NO}\right]}^2}{\left[\mathrm{NO}\right]\left[{\mathrm{O}}_2\right]}$= 1.6 x 10^-3

 $\frac{1}{2}{N}_2 + \frac{1}{2}{O}_2$

$\mathrm{Kc} = \frac{{\left[{\mathrm{N}}_2\right]}^{{\displaystyle \frac{1}{2}}}{\left[{\mathrm{O}}_2\right]}^{{\displaystyle \frac{1}{2}}}}{\left[\mathrm{NO}\right]}$

${\left(\frac{1}{{\mathrm{K}}_{\mathrm{c}}}\right)}^{\frac{1}{2}}={\left(\frac{1}{1.6\times {10}^{-3}}\right)}^{\frac{1}{2}}$

K_c = $\frac{{10}^2}{4}$ = 25

K_p = K_c

K_p=25

Therefore, the correct answer is 25.