og107

xiaoxuanchu

107. Last year all refuse collected by Shelbyville city
services was incinerated. This incineration generated
a large quantity of residual ash. In order to reduce the
amount of residual ash Shelbyville generates this year
to half of last year’s total, the city has revamped its
collection program. This year city services will
separate for recycling enough refuse to reduce the
number of truckloads of refuse to be incinerated to
half of last year’s number.
Which of the following is required for the revamped
collection program to achieve its aim?
(A) This year, no materials that city services could
separate for recycling will be incinerated.
(B) Separating recyclable materials from materials
to be incinerated will cost Shelbyville less than
half what it cost last year to dispose of the
residual ash.
(C) Refuse collected by city services will contain a
larger proportion of recyclable materials this
year than it did last year.
(D) The refuse incinerated this year will generate no
more residual ash per truckload incinerated than
did the refuse incinerated last year.
(E) The total quantity of refuse collected by
Shelbyville city services this year will be no
greater than that collected last year.

D is correct

完全不明白这个考点在哪， This year city services will
separate for recycling enough refuse to reduce the
number of truckloads of refuse to be incinerated to
half of last year’s number.和这个选项D有啥关联。

zhanghaolin

It is a necessary assumption question. Use negation method to find the correct answer choice.

City service will separte enough refuse for recycling purposes in order to reduce the total number of truckloads of refuse sent for inceineration by half. The intent is to convert at least half of the refuse for recycling in order to cut the total amount for incineration/burning in a year.

If you read carefully, you would notice a scope shift from "the amount of residual ash" to "the number of truck loads." For the conclusion to hold, D has to be true, since it connects "amount of ash" to "truckload." What if this year's truck increases its capacity to twice as much as last year? Then the city  will end up with equal amount of ash in the end.

xiaoxuanchu

懂了~谢谢呀
还有个问题，A选项OG上的解释看不明白呀，能不能解释下呀？
A This merely indicates that no further reduction of ash through recycling could be achieved this year; it indicates nothing about how much the ash will be reduced.