Two long conductors, separated by a distance $$d$$ carry current $$I_1$$ and $$I_2$$ in the same direction. They exert a force $$F$$ on each other. Now the current in one of them increased to two times and its direction reversed. The distance is also increased to $$3d$$. The new value of the force between them is

A

$$-2F$$

B

$$F/3$$

C

$$-2F/3$$

D

$$-F/3$$