$(I)$ ટોલ્યુઈન                                                         $(II)$ $m-$ ડાયક્લોરોબેન્ઝિન

$(III)$ $o-$ ડાયક્લોરોબેન્ઝિન                                  $(IV)$ $p-$ ડાયક્લોરોબેન્ઝિન

$\,\begin{array}{*{20}{c}}
{C{H_3} - CH - C{H_2} - CH - C{H_2} - C{H_3}}\\
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,|\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,|\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,}\\
{\,\,\,\,\,\,\,\,\,Br\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,Br\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,}
\end{array}$ $\xrightarrow[{heat}]{{KOH,\,C{H_3}OH}}$

$R - Br + C{l^ - }\xrightarrow{{DMF}}R - Cl + B{r^ - }$  ,

નીચેનામાંથી કઈ  એક રૂપરેખાંકનનું સંપૂર્ણ વિપરીત પસાર કરે છે?

${C_2}{H_5}I\xrightarrow{{Alco.\,\,KOH}}X\xrightarrow{{B{r_2}}}Y\xrightarrow{{KCN}}Z$