Two concentric conducting spheres of radii ${\mathrm{r}}_1$ and ${\text{r}}_{\text{2}}\left({\text{r}}_{\text{1}}{\text{ < r}}_{\text{2}}\right)$ carry electric charges of $+\mathrm{Q}$ and $-\mathrm{Q}$ respectively. The region between the sphere is filled with two insulating layers of dielectric constant ${\text{ε}}_1$ and ${\text{ε}}_2$ and width ${\mathrm{d}}_1$ and ${\mathrm{d}}_2$ respectively. Variation of the potential and electric field with radial distance from $\mathrm{O}$ is given. Select the correct one. (assume $\mathrm{V}$at $\mathrm{ }{\mathrm{r}}_2=0$ )