The correct order of nucleophilicity is
| A. |
`Cl^– > Br^– > I^– > OH^– > C_2H_5O^–` |
| B. |
`I^– > OH^– > Br^– > Cl^– > C_2H_5O^–` |
| C. |
`I^– > Br^– > Cl^– > OH^– > C_2H_5O^–` |
| D. |
`C_2H_5O^– > OH^– > Cl^– > Br^– > I^–` |
 |
Weaker the acid, stronger is the conjugate base and stronger is nucleophilicity. The order of nucleophilicity is `C_2 H_5O^– > OH^– > Cl^– > Br^– > I^–`