Internal Battery Resistance: the Emf and the Internal Resistance of a Battery

Internal battery resistance: The emf and the internal resistance of a battery are as shown in the figure. When the terminal voltage V_ab is equal to 17.4 V, what is the current through the battery, including its direction?

A) 6.8 A, from b to a
B) 8.7 A, from b to a
C) 6.8 A, from a to b
D) 8.7 A, from a to b
E) 16 A, from b to a