Which Nucleophilic Substitution Reaction Would Be Unlikely to Occur?
A) $\rightarrow$

Which nucleophilic substitution reaction would be unlikely to occur?

A) HO ^- + CH₃CH₂-I $\rightarrow$ CH₃CH₂-OH + I ^-
B) I ^- + CH₃CH₂-H $\rightarrow$ CH₃CH₂-I + H ^-
C) CH₃S ^- + CH₃-Br $\rightarrow$ CH₃S-CH₃ + Br ^-
D) All of the above would be unlikely to occur.
E) None of the above would be unlikely to occur.