Aldehyde And Ketone

Identify product \(\mathrm{C}\) in following conversion.

m - Hydroxy Benzaldehyde \(\xrightarrow[\text { [Protection of }-\mathrm{OH} \text { group] }]{\mathrm{C}_6 \mathrm{H}_5 \mathrm{CH}_2 \mathrm{Cl}}\) \(\mathrm{A} \xrightarrow{[\mathrm{O}]} \mathrm{B}\) \(\xrightarrow[\text { [deprotection of }-\mathrm{OH} \text { group] }]{}\) C