(Soln)(Soln)(Purple colour solution ppt.) Na2[Fe(C)5NO]+SO42−→No ppt. (Soln)(Soln) Note: PbSO4Ksp=2.5×1.−8 PbSKsp=3×10−28 which are not given in question As in question selective precipitation is asked PbS will be precipitate much easier than PbSO4 though both are insoluble. Hence answer should be (C) also along with (A)