The correct option is D 0.15
As we know, MnO−4 will only oxidise Fe2+ not Fe3+.
+7MnO−4++2Fe2+H+⟶+2Mn2+++3Fe3+
nf=(|Change in O.S.|)×Number of atoms
nfMnO−4=|+2−(+7)|×1=5
nfFe2+=|+3−(+2)|×1=1
From the law of equivalence,
Equivalents of Fe2+=Equivalents of MnO−4
nFe2+×1=1.0×150×51000
∴ nFe2+=0.75 mol
Mole fraction of FeSO4=Mole fraction of Fe2+=0.755=0.15