a
\( \begin{array}{*{20}{c}}
  {\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\, C{H_3}} \\ 
  {\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\, |} \\ 
  {C{H_3}C{H_2}CH = C - C{H_3}} 
\end{array}\) \( \xrightarrow {(i)O_3,(ii)Zn,H_2O}\) \(CH_3CH_2CHO\) \(+\) \(\begin{array}{*{20}{c}}
  {\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\, C{H_3}\,\,\,\,\,\,\,} \\ 
  {\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,|\,\,\,\,\,\,\,\,\,\,\,\,\,} \\ 
  {C{H_3} - C = O} 
\end{array}\)