In Etard reaction, the final product is

The correct answer is Option (1) → Aromatic aldehyde

Strong oxidising agents oxidise toluene all the way to benzoic acid. The oxidation can be stopped at the aldehyde stage with a reagent that converts the methyl group into an intermediate that is hard to oxidise further. In the Etard reaction, toluene is treated with chromyl chloride, \( \ce{CrO2Cl2} \), in \( \ce{CS2} \). The methyl group is oxidised to a chromium complex, which on hydrolysis gives benzaldehyde.

So the final product of the Etard reaction is an aromatic aldehyde.

NCERT (2026-27 edition):
Use of Chromyl Chloride (CrO₂Cl₂)