Aldehyde And Ketone

Identify the product '\(\mathrm{B}\)' in the following reaction. Toluene \(\xrightarrow[\mathrm{CS}_2]{\text { Chromylchloride }} \mathrm{A} \xrightarrow{\mathrm{H}_3 \mathrm{O}^{+}}\mathrm{B}\)