:Which one of the lanthanoids given below is the most stable in divalent form?

${\mathrm{E}}_{{\mathrm{M}}^{3+}/{\mathrm{M}}^{2+}}^{\mathrm{o}}\Rightarrow \begin{array}{cc}\mathrm{Eu}& \mathrm{Yb}\\ -0.35& -1.05\end{array}$
Hence, due to more reduction potential in Eu as 
compared to Yb, it can concluded that Eu²⁺ is more stable than Yb²⁺