题目选项分析

Highway Official: When resurfacing our concrete bridges, we should use electrically conductive concrete (ECC) rather than standard concrete. In the winter, ECC can be heated by passing an electric current through it, thereby preventing ice buildup. The cost of the electricity needed is substantially lower than the cost of the de-icing salt we currently use.Taxpayer: But construction costs for ECC are much higher than for standard concrete, so your proposal is probably not justifiable on economic grounds.

Which of the following, if true, could best be used to support the highway official's proposal in the face of the taxpayer's objection?

【选项】If ECC were to be used for a bridge surface, the electric current would be turned on only at times at which ice was likely to form.