A primary amine on reaction with alc.KOH and chloroform yields

When a primary amine on reaction with alc.KOH and chloroform an-isocyanide formed as a product. It is foul in smell.

Balanced chemical reaction

$\mathrm{R}-{\mathrm{NH}}_2+{\mathrm{CHCl}}_3+3\mathrm{KOH}\stackrel{\mathrm{\Delta }}{⟶}\mathrm{R}-\mathrm{NC}+3\mathrm{KCl}+3{\mathrm{H}}_2\mathrm{O}$

This reaction is known as the Isocyanide test.

Therefore, option A is correct.