$ArN _{2} Cl \overset{Cu / HCl}{\rightarrow} ArCl + N _{2}$ is known as


(image) $\xrightarrow{{[O]}}A\xrightarrow{{SOC{l_2}}}B\xrightarrow{{Na{N_3}}}C\xrightarrow{{Heat}}D$



(image) $\xrightarrow{{SOC{l_2}}}\,B\,\xrightarrow{{N{H_3}}}\,C$$\,\xrightarrow[{B{r_2}}]{{NaOH}}\,D$
$\mathop {C{H_3} - N{H_2}}\limits_{(P)} \,\,\,\,\,\,\,\,\,\,\,\mathop {Ph - N{H_2}}\limits_{(Q)} $