Three solid insulating spheres, each of radius \(R\) and uniform mass density \(\rho_m\), fall vertically through a viscous fluid in a region containing a uniform upward electric field of magnitude \(E\). The fluid exerts a resistive drag force \(F_d = b v\) on each sphere, where \(b\) is a constant. The volume charge densities \(\rho(r)\) of the spheres as a function of radial distance \(r\) from their centers (\(0 \le r \le R\)) are given in the table below.

Sphere	Volume Charge Density \(\rho(r)\)
I	\(\rho_0 \left(\dfrac{r}{R}\right)\)
II	\(\rho_0 \left(\dfrac{r}{R}\right)^2\)
III	\(\dfrac{3}{5}\rho_0\)

Assuming that the gravitational force on each sphere is greater than the electric force acting on it, which of the following correctly ranks the magnitudes of the downward terminal velocities \(v_I\), \(v_{II}\), and \(v_{III}\) of the three spheres?