In the following sequence of reactions: Toluene →KMnO4 A →SOCl2 B →H2/Pd C; then product C is:

The oxidation of toluene with KMnO4 gives benzoic acid. Thionyl chloride converts the carboxylic group to an acid chloride. Reaction with hydrogen in the presence of palladium and barium sulphate gives benzaldehyde. Option C is correct.