Phthalimide is treated with KOH to give A. A is heated with bromoethane to give B. B is hydrolysed with aqueous NaOH (heat) to give amine C. C is heated with $\mathrm{CHCl}{}_3$ and alcoholic KOH to give D. D is

1. A$\mathrm{CH}{}_3\mathrm{CH}{}_2\mathrm{CN}$
2. B$\mathrm{CH}{}_3\mathrm{CH}{}_2\mathrm{NH}{}_2$
3. C$\mathrm{CH}{}_3\mathrm{CH}{}_2\mathrm{NHCHO}$
4. D$\mathrm{CH}{}_3\mathrm{CH}{}_2\mathrm{NC}$