Which of the following metals can be used for precipitation of silver from sodium argentocyanide solution

• Silver and gold are extracted by the cyanide process also called the Mac Arthur - Forrest process. After the preliminary crushing and concentration by the froth floatation process, the ore (crushed auriferous rocks in the case of gold) is leached with a dilute (0.4 - 7%) solution of sodium cyanide which is made alkaline by adding lime kept agitated by a current of air. Silver (or gold) passes into the solution as argento cyanide (or aurocyanide):

                  ${\mathrm{Ag}}_2 \mathrm{S}+4\mathrm{NaCN}\to 2\mathrm{Na}\left[\mathrm{Ag}(\mathrm{CN}{)}_2\right]+{\mathrm{Na}}_2 \mathrm{S}$

Silver is obtained by reaction with Zn:

              $2\mathrm{Na}\left[\mathrm{Ag}(\mathrm{CN}{)}_2\right]+\mathrm{Zn}\to {\mathrm{Na}}_2\left[\mathrm{Zn}(\mathrm{CN}{)}_4\right]+2\mathrm{Ag}$

Therefore, Option A is the correct answer.