The dissociation constant of a substituted benzoic acid at $25C$ is $1.0 \times 10^{-4}$. The $p^{H}$ of $0.01\;M$ solution its sodium salt is

Question

$\begin{array}{1 1} (a)\;0 \\(b)\;1 \\ (c)\;7 \\ (d)\;8 \end{array} $