Wires A and B have have identical lengths and have circular cross-sections. The radius of A is twice the radius of B i.e. `R_A = 2R_B`. For a given temperature difference between the two ends, both wires conduct heat at the same rate. The relation between the thermal conductivities is given by-
A. `K_(A)=4K_(B)`
B. `K_(A)=2K_(B)`
C. `K_(A)=K_(B)//2`
D. `K_(A)=K_(B)//4`
