d
\(\underset{(A)}{\mathop{\begin{matrix}
   \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,O  \\
   \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,||  \\
   C{{H}_{3}}C{{H}_{2}}-C-OH  \\
\end{matrix}}}\,\)  \(\xrightarrow{N{{H}_{3}}}\,\underset{(B)}{\mathop{C{{H}_{3}}C{{H}_{2}}COON{{H}_{4}}}}\,\xrightarrow{\Delta }\) 

\(\underset{(C)}{\mathop{\begin{matrix}
   \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,O  \\
   \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,||  \\
   C{{H}_{3}}-C{{H}_{2}}-C-N{{H}_{2}}  \\
\end{matrix}}}\,\)  \(\xrightarrow[\begin{smallmatrix} 
 Hofmann's\,\,broamide \\ 
 reaction 
\end{smallmatrix}]{B{{r}_{2}}\,,\,KOH}\)  \(C{{H}_{3}}-C{{H}_{2}}-N{{H}_{2}}\)