The specific reaction scheme and the structures of the options are missing from the provided text. However, a characteristic reaction of aniline that yields a coloured product is the azo coupling reaction. Aniline first reacts with nitrous acid ($NaNO_2 + HCl$) at 0-5 °C to form benzene diazonium chloride. This diazonium salt then acts as an electrophile and couples with electron-rich aromatic rings (like phenol or another aniline molecule) to form highly coloured azo compounds (dyes) characterized by the $-N=N-$ linkage.