Two resistance `R_(1)` and `R_(2)` are made of different material. The temperature coefficient of the material of `R_(1)` is `alpha` and of the material of `R_(2)` is `-beta`. Then resistance of the series combination of `R_(1)` and `R_(2)` will not change with temperature, if `R_(1)//R_(2)` will not change with temperature if `R_(1)//R_(2)` equals
A. `alpha/beta`
B. `(alpha+beta)/(alpha-beta)`
C. `(alpha^(2) + beta^(2))/(alphabeta)`
D. `beta/alpha`
