The cyanide process of gold extraction involves leaching out gold from its ore with $CN^{-}$ in the presence of $Q$ in water to form $R$. Subsequently,$R$ is treated with $T$ to obtain $Au$ and $Z$. Choose the correct option$(s)$.
$1$. $T$ is $Zn$
$2$. $R$ is $[Au(CN)_2]^-$
$3$. $Z$ is $[Zn(CN)_4]^{2-}$
$4$. $Q$ is $O_2$

• A
  $1, 2, 3$
• B
  $1, 2, 4$
• C
  $1, 3, 4$
• D
  $1, 2, 3, 4$