CH _ 3 Br+Nu^ - CH _ 3 - Nu+Br^ - The decreasing order of the rate...

\mathrm{CH}}_{3} \mathrm{Br}+\mathrm{Nu}^{-} \longrightarrow \mathrm{CH}}_{3}-\mathrm{Nu}+\mathrm{Br}^{-}$The decreasing order of the rate of the above reaction with nucleophiles \left(\mathrm{Nu}^{-}\right) \mathrm{A}$ to $\mathrm{D}$ is \left[\mathrm{Nu}^{-}=(\mathrm{A}) \mathrm{PhO}^{-}\right.$, (B)$\mathrm{AcO}^{-}$, (C)$\mathrm{HO}^{-}$, (D) \left.\mathrm{CH}_3 \mathrm{O}^{-}\right]$