An aromatic compound 'A' having molecular formula $\mathrm{C}_7 \mathrm{H}_6 \mathrm{O}_2$ on treating with aqueous ammonia and heating forms compound ' B '. The compound ' B ' on reaction with molecular bromine and potassium hydroxide provides compound ' C ' having molecular formula $\mathrm{C}_6 \mathrm{H}_7 \mathrm{~N}$. The structure ' A ' is :