a
\(\underset{(A)}{\mathop{\begin{matrix}
C{{H}_{3}}-CH-N{{H}_{2}} \\
|\,\,\,\,\,\, \\
\,C{{H}_{3}} \\
\end{matrix}}}\,\) \(\xrightarrow[KOH]{CHC{{l}_{3}}}\) \(\underset{(C)}{\mathop{\begin{matrix}
C{{H}_{3}}-CH-N\vec{=}C \\
|\,\,\,\,\,\,\,\, \\
C{{H}_{3}}\, \\
\end{matrix}}}\,\) \(\xrightarrow{\operatorname{Re}duction}\) \(\begin{matrix}
C{{H}_{3}}-CH-NH-C{{H}_{3}} \\
\,\,|\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\, \\
\,\,C{{H}_{3\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,}}\,\, \\
\end{matrix}\)