The following equilibrium constant are given : $N_2+3H_2 \rightleftharpoons 2NH_3;K_1 \\ N_2+O_2 \rightleftharpoons 2NO;K_2\\H_2+1/2O_2 \rightleftharpoons +H_2OK_3 $ The equilibrium constants for the oxidation of $NH_3$ by oxygen to given NO is :

Question

$\begin{array}{1 1} (a)\;K_2K_3^3/K_1 \\(b)\;KK_2K_3^2/K_1\\ (c)\;K_2^2K_3/K_1 \\ (d)\;K_1K_2/K_3 \end{array} $