A spherical conductor A contains two spherical cavities. The total charge on the conductor itself is zero. However, there is a point charge `q_b` at the centre of one cavity and `q_c` at the centre of the other. At considerable distance r away from the centre of the spherical conductor, there is another charge `q_d`. Forces acting on `q_b, q_c and q_d` are `F_1, F_2, and F_3`, respectively. [Assume all charges are positive.]
A. `F_1ltF_2ltF_3`
B. `F_1=F_2ltF_3`
C. `F_1=F_2gtF_3`
D. `F_1gtF_2gtF_3`
