Calculate the stability constant of the complex $[Zn(NH_3)_4]^{2+}$ formed in the $rx_n$:$Zn^{2+}+4NH_3\rightleftharpoons[Zn(NH_3)_4]^{2+}$. The stability constant 'K' is

Question

Given :

$E^{\large\circ}_{Zn^{2+}/Zn}=-0.76V$

$E^{\large\circ}_{Zn(NH_{34}^{2+}/Zn^{\large\circ}}=-1.03V$

$\begin{array}{1 1}(A)\;3\times 10^{10}&(B)\;1.38\times 10^9\\(C)\;2.28\times 10^9&(D)\;9.1\times 10^6\end{array}$