Which has maximum $\mathrm{pH}$

The hydrogen's potential or power is expressed in pH . While basic solution has larger concentrations of $O{H}^{-}$ ions and is thought to have higher pH values, acidic solution has higher concentrations of  $H^{+}$ ions and is thought to have lower pH values. The pH scale now ranges from 1 to 14, and a substance with a pH value of 7 or lower is considered neutral. A compound with a pH value of 7 or higher is termed basic. More basic a compound is, the higher its marking on the pH scale; more acidic a compound is, the lower its marking on the pH scale.

We are given four possibilities in the aforementioned question, all of which have the same molar concentration, or 0.01M. According to the justification provided, options A and B—$H_{2}S{O}_4$ and HCl—have the lowest pH values since they are both strong acids. We are given the bases $Ca{\left(OH\right)}_2$ and NaOH in options C and D, and because the calcium hydroxide molecule may donate two hydroxide ions, it has a higher concentration of OH ions and thus the highest pH value.

Therefore, the correct option is (C).