The insulated spheres of radii `R_(1)` and `R_(2)` having charges `Q_(1)` and `Q_(2)` respectively are connected to each other. There is
A. an increase in the energy of the system
B. no change in the energy of the system
C. always decrease in energy
D. a decrease in energy of the system unless `Q_(1)R_(2)=Q_(2)R_(1)`
