$(A)$ $\begin{matrix}
O\,\,\,\,\,\,\,\,\,\, \\
||\,\,\,\,\,\,\,\,\,\,\,\, \\
R-C-NHBr \\
\end{matrix}$ $(B)$ $R-NH-Br$
$(C)$ $R-N=C=O$ $(D)$ $\begin{matrix}
\,\,\,\,O\,\,\,\,\,\,\,\,\,\, \\
\,\,\,\,\,\,||\,\,\,\,\,\,\,\,\,\,\,\, \\
R-C-NB{{r}_{2}} \\
\end{matrix}$


