Q4:
In the past the country of Siduria has relied heavily on imported oil. Siduria recently implemented a program to convert heating systems from oil to natural gas. Siduria already produces more natural gas each year than it burns, and oil production in Sidurian oil fields is increasing at a steady pace. If these trends in fuel production and usage continue, therefore, Sidurian reliance on foreign sources for fuel should decline soon.
Which of the following is an assumption on which the argument depends?
- In Siduria the rate of fuel consumption is rising no more quickly than the rate of fuel production.
- Domestic production of natural gas is rising faster than is domestic production of oil in Siduria.
- No fuel other than natural gas is expected to be used as a replacement for oil in Siduria.
- Buildings cannot be heated by solar energy rather than by oil or natural gas.
- All new homes that are being built will have natural-gas-burning heating systems.
答案是A.
我的问题:
"Siduria already produces more natural gas each year than it burns, and oil production in Sidurian oil fields is increasing at a steady pace. If these trends in fuel production and usage continue",
如果天然气总是生产的比使用的多,那不就是说已经把A排除了吗?
我选了C,尽管有些勉强.
理由:题中结论是"Sidurian reliance on foreign sources for fuel should decline soon",但这个fuel 不一定等同于Gas或Oil. 感觉上像个逻辑上常见的考点:概念变化.
假如C成立,那可能该国还计划用别的燃料代替石油,如果这种燃料也可能是进口来的,就不能得出结论了.
感觉GMAT逻辑思路总是不那么清晰.答案有时不是那么有说服力.如果这题没有"If these trends in fuel production and usage continue"这句话,我绝对会选A.
请NN指点一下.多谢! |