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 taxpayer’s objection?



(A) The use of de-icing salt causes corrosion of the reinforcing steel in concrete bridge decks and damage to the concrete itself, thereby considerably shortening the useful life of concrete bridges.


(B) Severe icing conditions can cause power outages and slow down the work of emergency crews trying to get power restored.


(C) In weather conditions conducive to icing, ice generally forms on the concrete surfaces of bridges well before it forms on parts of the roadway that go over solid ground.


(D) Aside from its potential use for de-icing bridges, ECC might also be an effective means of keeping other concrete structures such as parking garages and airport runways ice free.


(E) 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.



Let’s look at the highway official’s argument-


Premises


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.


Conclusion/opinion 


When resurfacing our concrete bridges, we should use electrically conductive concrete (ECC) rather than standard concrete.


Now, let’s look at the taxpayer’s argument


Premises


construction costs for ECC are much higher than for standard concrete,


Conclusion/opinion

so your proposal is probably not justifiable on economic grounds.



We need to find an option that would support the highway official’s proposal in the face of taxpayer’s objection.


(A) The use of de-icing salt causes corrosion of the reinforcing steel in concrete bridge decks and damage to the concrete itself, thereby considerably shortening the useful life of concrete bridges.



De-icing salt is what we currently use. Option A says that the use of de-icing salt causes corrosion of the reinforcing steel in concrete bridge decks and damage to the concrete itself, thereby considerably shortening the useful life of concrete bridges. This strengthens the highway official’s proposal that When resurfacing our concrete bridges, we should use electrically conductive concrete (ECC) rather than standard concrete. ECC can be heated by passing an electric current through it, thereby preventing ice buildup. Correct.


(B) Severe icing conditions can cause power outages and slow down the work of emergency crews trying to get power restored.


Irrelevant. The conclusion is related to the use of ECC. Eliminate


(C) In weather conditions conducive to icing, ice generally forms on the concrete surfaces of bridges well before it forms on parts of the roadway that go over solid ground.


Same as B. Eliminate.


(D) Aside from its potential use for de-icing bridges, ECC might also be an effective means of keeping other concrete structures such as parking garages and airport runways ice free.


When resurfacing our concrete bridges, we should use electrically conductive concrete (ECC) rather than standard concrete.

parking garages and airport runways ice free- Out of scope


(E) 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.


Does not matter. Eliminate.