Two cells of emfs $2.0\text{ V}$ and $6.0\text{ V}$ and internal resistances $0.1\text{ }\Omega$ and $0.4\text{ }\Omega$ respectively, are connected in parallel. The equivalent emf of the combination will be : (A) $2.0\text{ V}$ (B) $2.8\text{ V}$ (C) $6.0\text{ V}$ (D) $8.0\text{ V}$