The dissociation equilibrium of a gas \(\mathrm{AB}_{2}\) can be represented as:
$$
2 \mathrm{AB}_{2(g)} \leftrightharpoons 2 \mathrm{AB}_{(g)}+\mathrm{B}_{2(g)}
$$
The degree of dissociation is \(x\) and is small compared to 1 . The expression relating the degree of dissociation \((x)\) with equilibrium constant \(K_{p}\) and total pressure \(P\) is
(a) \(\left(2 K_{p} / P\right)^{1 / 2}\)
(b) \(\left(K_{p} / P\right)\)
(c) \(\left(2 K_{p} / P\right)\)
(d) \(\left(2 K_{p} / P\right)^{1 / 3}\)