A colourless substance ' A′(C6H7 N) is sparingly soluble in water and gives a water soluble compound ' B ' on treatment with mineral acid. On reacting with CHCl3 and alcoholic potash 'A' produces an obnoxious smell due to the formation of compound ' C '. Reaction of 'A' with benzenesulphonyl chloride gives compound ' D ' which is soluble in alkali. With NaNO₂ and, ' A ' forms compound ' E ' which reacts with phenol in alkaline medium to give an orange dye ' F ' Identify compounds ' A ' to ' F '.