Many industrialized nations are trying to reduce atmospheric concentrations of carbon dioxide, a gas released by the burning of fossil fuels. One proposal is to replace conventional cement, which is made with calcium carbonate, by a new “eco-cement.” This new cement, made with magnesium carbonate, absorbs large amount of carbon dioxide when exposed to the atmosphere. Therefore, using eco-cement for new concrete building projects will significantly help reduce atmospheric concentrations of carbon dioxide.
Which of the following, if true, most strengthens the argument?
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AThe cost of magnesium carbonate, currently greater than the cost of calcium carbonate, probably will fall as more magnesium carbonate is used in cement manufacture.
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BEco-cement is strengthened when absorbed carbon dioxide reacts with the cement.
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CBefore the development of eco-cement, magnesium-based cement was considered too susceptible to water erosion to be of practical use.
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DThe manufacture of eco-cement uses considerably less fossil fuel per unit of cement than the manufacture of conventional cement does.
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EMost building-industry groups are unaware of the development or vailability of eco-cement.
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