Leaching of ${\mathrm{Ag}}_2\mathrm{S}$ is carried out by heating it with a dilute solution of:

Leaching of ${\mathrm{Ag}}_2\mathrm{S}$ is carried out by heating it with a dilute solution of $\mathrm{NaCN}$ in the presence of $O_2$. Heating ${\mathrm{Ag}}_2\mathrm{S}$ in the presence of a diluted NaCN solution allows for the leaching of ${\mathrm{Ag}}_2\mathrm{S}$. This creates a fluid complex $\left[\mathrm{Ag}\right(\mathrm{CN}{)}_2{]}^{-}$. ${\mathrm{Ag}}_2\mathrm{S}+4\mathrm{NaCN}\rightleftharpoons 4{\mathrm{Na}}^{+}+2\left[\mathrm{Ag}\right(\mathrm{CN}{)}_2{\left]}^{\right(}2-)+{\mathrm{S}}^{(}2-)$

Here, oxygen converts sulfide ions to sulfate ions.

So, it is possible to segregate soluble and insoluble materials.

Silver is produced in a displacement reaction when the cyanide molecule is treated with zinc. $2\mathrm{Na}\left[\mathrm{Ag}(\mathrm{CN}{)}_2\right]+\mathrm{Zn}\to {\left[\mathrm{Zn}(\mathrm{CN}{)}_4\right]}^{2-}+2\mathrm{Ag}\downarrow$ 

Hence Correct option is D.