Which of the following reactions is not an example of nucleophilic addition–elimination reaction?

Nucleophilic addition-elimination reactions are characteristic of aldehydes and ketones when they react with ammonia derivatives ($H_2N-Z$). In these reactions, the nucleophile attacks the carbonyl carbon to form an intermediate (addition step), which subsequently loses a water molecule (elimination step) to form the final product containing a $C=N$ double bond (e.g., oximes, hydrazones, semicarbazones).

Conversely, reactions like the addition of HCN to form cyanohydrins or sodium hydrogen sulphite ($NaHSO_3$) to aldehydes are examples of simple Nucleophilic Addition reactions where no small molecule is eliminated. Similarly, reactions of haloalkanes are typically Nucleophilic Substitutions ($S_N1$ or $S_N2$), and reactions of benzene are Electrophilic Substitutions. Without the specific reaction structures in the options, the exact nature of Option 1 cannot be confirmed, but it must describe a mechanism other than the addition-elimination pathway described above.