Given that $C+O_2 \rightarrow CO_2;\: \: \: \: \: \Delta H^{\circ} = -x\: kJ\: and\: 2CO+O_2 \rightarrow 2CO_2; \: \: \: \: \:\Delta H^{\circ} = -y\: kJ$ The standard enthalpy of formation of carbon monoxide is

Question

$\begin {array} {1 1} (A)\;y-2x & \quad (B)\;\large\frac{(2x-y)}{2} \\ (C)\;\large\frac{(y-2x)}{2} & \quad (D)\;2x-y \end {array}$