Two rods of the same length and diameter having thermal conductivities `K_1` and `K_2` are joined in parallel. The equivalent thermal conductivity of combination is

Options

A. `(K_1 K_2)/(K_1 + K_2)`
B. `(K_1 + K_2)`
C. `(K_1 + K_2)/2`
D. `sqrt(K_1 K_2)`

Answer

C