Which nucleophilic substitution reaction is not likely to occur? (This would be true regardless of whether one was using a polar aprotic or polar protic solvent)
A. I⁻ + CH₃CH₂-OH –> CH₃CH₂-I⁻ + OH⁻
B. CH₃0⁻ + CH₃CH₂-Br –> CH₃CH₂-OCH₃ + Br⁻
C. I⁻ + CH₃CH₂-Br –> CH₃CH₂-I + Br⁻
D. I⁻ + CH₃CH₂-Cl -> CH₃CH₂-I + Cl⁻
E. OH⁻ + CH₃CH₂-Cl –> CH₃CH₂-OH + Cl⁻