A spherical solid ball of volume $$V$$ is made of a material of density $$\rho_1$$. It is falling through a liquid of density $$\rho_2\ (\rho_2 < \rho_1)$$. Assume that the liquid applies a viscous force on the ball that is proportional to the square of its speed v, i.e., $$F_{viscous} = -kv^2 (k > 0)$$. The terminal speed of the ball is

A

$$\sqrt{\frac{Vg(\rho_1 - \rho_2)}{k}}$$

B

$$\frac{Vg\rho_1}{k}$$

C

$$\sqrt{\frac{Vg\rho_1}{k}}$$

D

$$\frac{Vg(\rho_1 - \rho_2)}{k}$$