The graph that correctly indicates the titration curve of $(N{H}_{4}OH+HCl)$ titration (y-axis = conductance, x -axis = volume of base added)

$(H^{+}+C{l}^{-})+(N{H}_4^{+}+O{H}^{-})\to (N{H}_4^{+}+C{l}^{-})+H_{2}O$

It indicates during the neutralization fastly moving $H^{+}$ ions are replaced by slowly moving $N{H}_4^{+}$ ions.  Therefore, conductivity decreases ( $\downarrow es$ ) and it is continued till whole of strong acid is neutralized. After neutralization, If further amount of base from buratte is added conductance remains constant