Under what conditions, can the current passing through the resistance R be increased? r1 and r2 are the internal resistances of the two batteries.

Question

 

$\begin {array} {1 1} (A)\;E_2r_1 > E_1(R + r_2) & \quad (B)\; E_1r_2 > E_2(R + r_1) \\ (C)\;E_2r_2 < E_1(R + r_2) & \quad (D)\;E_1r_1 > E_2(R + r_1) \end {array}$