The standard electrode potential for $\text{Sn}^{4+}/\text{Sn}^{2+}$ couple is $+ 0.15 \text{ V}$ and for $\text{Cr}^{3+}/\text{Cr}$ couple is $- 0.73 \text{ V}$. These two couples are connected to make an electrochemical cell. The redox reaction is spontaneous. The cell potential will be : (A) $+ 0.88 \text{ V}$ (B) $+ 0.58 \text{ V}$ (C) $- 0.88 \text{ V}$ (D) $- 0.58 \text{ V}$