GWD-6-32

这题很多人都倾向于D，但是E是不是更好？因为E说通过recycle，methane的排放可以减少。 请nn帮忙看看。谢谢。

Q32:

Proposal:  Carbon dioxide and methane in the atmosphere block the escape of heat into space.  So emission of these “greenhouse” gases contributes to global warming.  In order to reduce global warming, emission of greenhouse gases needs to be reduced.  Therefore, the methane now emitted from open landfills should instead be burned to produce electricity.

Objection:  The burning of methane generates carbon dioxide that is released into the atmosphere.

Which of the following, if true, most adequately counters the objection made to the proposal?

1. Every time a human being or other mammal exhales, there is some carbon dioxide released into the air.


2. The conversion of methane to electricity would occur at a considerable distance from the landfills.


3. The methane that is used to generate electricity would generally be used as a substitute for a fuel that does not produce any greenhouse gases when burned.


4. Methane in the atmosphere is more effective in blocking the escape of heat from the Earth than is carbon dioxide.


5. The amount of methane emitted from the landfills could be reduced if the materials whose decomposition produces methane were not discarded, but recycled.

E  out of scope

建议：用某方法达到某目的

         方法：垃圾堆跑出的甲烷用去燃烧发电，不让它跑到大气构成GREEN HOUSE GAS

        目的：减少温室效应

反对意见：燃烧甲烷会产生二氧化碳（它一样构成GREEN HOUSE GAS），所以目的达不到

D的意思为：虽然都是GREEN HOUSE GAS，但甲烷对温室效应影响大于二氧化碳。用小害换大害。所以WEAKEN

E。将那些产生甲烷的垃圾再循环，以达到甲烷减少的目的。这是提出另外一种解决方法。并没有WEAKEN反对意见。他们在讨论将垃圾堆产生的甲烷用去发电能否达到减少GREEN HOUSE GAS。