Correct Answer - `CIO^(-)` has `17+8+1=26` electrons. A neutral molecule with `26` electrons is `OF_(2)(8+2xx9=26` electrons) Alternatively, replace `O^(-)` (`9` electrons) in `CIO^(-)` by `F` (`9` electrons).The resulting molecule is `CIF`.Since `Cl` in `CIF` can further donate electrons to two more `F` atoms to form `CIF_(3)`, therefore, `CIF` is a Lewis base.