Ferric ferrocyanide /Potassium ferrocyanide/ Sodium ferrocyanide is prussian blue.
Fe4[Fe(CN)6]3
Option D is correct,
In the Lassaigne’s test for nitrogen in an organic compound, the Prussian blue colour is obtained due to the formation of:
(a) Na4[Fe(CN)6] (b) Fe4[Fe(CN)6]3 (c) Fe2[Fe(CN)6] (d) Fe3[Fe(CN)6]4