# Sinks of carbon monoxide $2CO+O_2\qquad \underrightarrow {soil}\qquad x$.$CO+3H_2\qquad\underrightarrow{soil}\qquad y+z$.The $z$ in the equation is

$\begin{array}{1 1}(a)\;H_2O\\(b)\;H_3O\\(c)\;O_2\\(d)\;CO_2\end{array}$

The z in the equation is $H_2O$
Hence (a) is the correct answer.