The compound shown is refluxed with dilute aqueous $\mathrm{H}{}_2\mathrm{SO}{}_4$ for several hours. Which structure is the organic product?

The compound is 3-methylbutanenitrile. Prolonged acid hydrolysis converts the nitrile through the amide to the carboxylic acid, 3-methylbutanoic acid, and the nitrogen leaves as $\mathrm{NH}{}_4{}^{+}$. The amide is only an intermediate, the amine requires reduction, and the aldehyde needs DIBAL-H.