Sodium fusion extract, obtained from aniline, on treatment with iron(II) sulphate and $$H_2SO_4$$ in presence of air gives a Prussian blue precipitate. The blue colour is due to the formation of

A

$$Fe_4[Fe(CN)_6]_3$$

B

$$Fe_3[Fe(CN)_6]_2$$

C

$$Fe_4[Fe(CN)_6]_2$$

D

$$Fe_3[Fe(CN)_6]_3$$