For $(i) I^-, (ii) Cl^{-}, (iii) Br^{-} $. The increasing order of nuclephilicity would be :

Question

$(a)\;Cl^{-} < Br^- < I^- \\ (b)\;I^{-} < Cl^- < Br^- \\(c)\; Br^{-} < Cl^- < I^- \\ (d)\;I^{-} < Br^- < Cl^- $