In a reaction of aniline a coloured product C was obtained. ext The structure of C would be

Step-by-step solution

Key Idea : 1^ amines form diazonium salts at low temperature and diazonium salts are weak electrophiles, so react with strongly activated ring. (takes H from benzene nucleus). Note : The - N = N - linkage is called -azo linkage, and the reactions in which azo or diazo compounds are formed, are called diazo coupling reactions.