Electric Field and Potential : the Graph in the Figure

Electric field and potential : The graph in the figure shows the variation of the electric potential V (measured in volts) as a function of the radial direction r (measured in meters) . For which range or value of r is the magnitude of the electric field the largest?

A) from r = 0 m to r = 3 m
B) from r = 3 m to r = 4 m
C) from r = 4 m to r = 6 m
D) at r = 3 m
E) at r = 4 m