Identify compound X in the following sequence of reactions: 

Toluene reacts with chlorine in presence of sunlight to give Benzalchloride through free radical substitution ;

This on alkaline hydrolysis gives Benzaldehyde.;

${\mathrm{C}}_6{\mathrm{H}}_5-{\mathrm{CH}}_3 \stackrel{{\mathrm{Cl}}_2/\mathrm{h\nu }}{\to } {\mathrm{C}}_6{\mathrm{H}}_5-{\mathrm{CHCl}}_2 \stackrel{{\mathrm{H}}_2\mathrm{O}/373 \mathrm{K}}{\to } \left[{\mathrm{C}}_6{\mathrm{H}}_5\mathrm{CH}{\left(\mathrm{OH}\right)}_2\right]\stackrel{-{\mathrm{H}}_2\mathrm{O}}{\to } {\mathrm{C}}_6{\mathrm{H}}_5\mathrm{CHO};$