Consider the reaction $RCHO+NH_2NH_2 \to RCH = NH_2$ What sort of reaction is it ?

Question

$\begin{array}{1 1} \text{Electrophilic addition elimination reaction } \\ \text{Free radical addition elimination reaction } \\ \text{electrophilic substitution elimination reaction } \\ \text{Nucleophilic addition elimination reaction } \end{array} $