Five rods of same dimensions are arranged as shown in the figure. They have thermal conductivities `K _(1) , K_(2) , K _(3) , K_( 4)` and `K_( 5)` . When points A and B are maintained at different temperatures, no heat flows through the central rod if
A. `K_(1) = K_(4) and K_(2) = K_(3)`
B. `K_(1)K_(4) = K_(2)K_(3)`
C. `K_(1)K_(2) = K_(3)K_(4)`
D. None of the above