Passage 2
Imagine a world in which everyone uses all the energy they want, yet dependence on oil, with its attendant smog and green-house-gas emissions, is a thing of the past. This utopia is plausible—many would say probably. It is one in which hydrogen, rather than fossil fuels, is central to our energy economy.
Vehicles could use hydrogen in a variety of ways. Some researchers favor the introduction of electric cars powered solely by fuel cells, which combine hydrogen and oxygen to produce electricity. Others say that conventional car engines can be converted to run on hydrogen with relatively minor modifications. Experts are also split over whether, as a temporary step towards a full hydrogen economy, vehicles should initially use on-board equipment to extract hydrogen from fossil fuels.
Infrastructure issues play a big role in the debate over which approach should be taken. The lack of an existing system for storing and distributing hydrogen presents a dilemma. Car manufacturers do not want to sell vehicles that people cannot fuel, and energy companies do not want to spend money developing a hydrogen distribution infrastructure when there are no hydrogen cars on the road. The equation becomes more complicated with fuel cells because they have yet to be produced in large numbers and their long-term reliability has not been proven.
This deadlock could be broken by “reformers”, which would allow hydrogen cars to run on fossil fuels. Reformers can break down the hydrocarbons in fossil fuels and so liberate hydrogen. Natural gas, for example, can be reformed by heating it together with water and a nickel-based catalyst. The result is a series of reactions whose products are carbon dioxide and hydrogen. Other fossil fuels, including petrol or gasoline, can be reformed in a similar way.
Hydrogen cars fitted with reformers would still run on petrol, but would reform it into hydrogen. Advocates of the technology say that this would give car companies the confidence to produce the vehicles, and so provide a fresh impetus for fuel-cell development. Several car manufacturers, including General Motors and DaimlerChrysler, are now working with Ballard Power Systems, a fuel-cell producer based in Burnaby, near Vancouver, to develop vehicles that are powered by fuel cells fed by reformers.
But reformers still produce carbon dioxide, and for many environmentalists, this is enough to rule them out. In addition, it has to be taken into account that hydrogen vehicles with reformers are also technologically more complex and costly to build than straight fuel-cell cars.
In this article, what is introduced as the most promising substitute for fossil fuels?
文章第一段最后一句提到“It is one in which hydrogen, rather than fossil fuels, is central to our energy economy”。由此可知，化石燃料最理想的替代品是氢气。故选C。
Car manufacturers and energy companies are reluctant in the energy reform campaign mainly because ________.
文章第三段第一句提到“Infrastructure issues play a big role in the debate over which approach should be taken.”。由此可知，基础设施建设是汽车制造商和能源公司不愿意进行能源改革的原因。故选B。
Which is NOT included as the problems with the “reformers”?
文章第五段第一句提到“...allow hydrogen cars to run on fossil fuels”，可以在氢气汽车使用化石燃 料，故A项正确；第五段第二句提到“...and so provide a fresh impetus for fuel-cell development”，为燃料电池 的发展提供新的动力，故B项正确；最后一段第一句提到“But reformers still produce carbon dioxide”，改装 版也会产生二氧化碳，故C项正确；最后一段最后一句提到“...hydrogen vehicles with reformers are also technologically more complex and costly to build than straight fuel-cell cars.”改良版的氢气汽车在技术上要比普 通的燃料汽车更复杂也更费力，并未提及价格更贵。故选D。
Why did General Motors and DaimlerChrysler favor reformers?
倒数第二段第二句提到“Advocates of the technology say that this would give car companies the confidence to 改良版的氢气汽车是因为他们对燃料电池的发展有信心。故选A。
The main idea of this article is ________.
综合全文，文章主要讲的是对新能源汽车的展望，着重介绍了改良版的氢气汽车，同时也指出改 良版也还面临着各种问题。故选A。