Two conductors have the same resistance at `0^@C` but their temperature coefficient of resistanc are `alpha_1 and alpha_2`. The respective temperature coefficients of their series and parallel combinations are nearly

A. `(alpha_(1)+alpha_(2))/2,alpha_(1)+alpha_(2)`

B. `alpha_(1)+alpha_(2),(alpha_(1)+alpha_(2))/2`

C. `alpha_(1)+alpha_(2),(alpha_(1)alpha_(2))/(alpha_(1)+alpha_(2))`

D. `(alpha_(1)+alpha_(2))/2,(alpha_(1)+alpha_(2))/2`