一道Bibble上的逻辑题，求解答

sophia王晗

3. There is relatively little room for growth in the
overall carpet market, which is tied to the size of the
population. Most who purchase carpet do so only
once or twice, first in their twenties or thirties, and
then perhaps again in their fifties or sixties. Thus as
the population ages, companies producing carpet
will be able to gain market share in the carpet market
only through purchasing competitors, and not
through more aggressive marketing.
Which one of the following, if true, casts the most
doubt on the conclusion above?
（A) Most of the major carpet producers market
other floor coverings as well.
(B) Most established carpet producers market
several different brand names and varieties,
and there is no remaining niche in the
market for new brands to fill.
(C) Two of the three mergers in the industry’s last
ten years led to a decline in profits and
revenues for the newly merged companies.
(D) Price reductions, achieved by cost-cutting in
production, by some of the dominant firms
in the carpet market are causing other
producers to leave the market altogether.
(E) The carpet market is unlike most markets in
that consumers are becoming increasingly
resistant to new patterns and styles.
Bibble上对于C选项的解释如下。我对第二点不是特别明白
Answer choice (C): This attractive answer is wrong for two very strong
reasons:
1. A Shell Game is played with the details of the conclusion. The
conclusion is about market share. Answer choice (C) is about a
decline in profits and revenues. The two are not the same, and so the
information in the answer choice does not weaken the conclusion.
2. Even if you assume that market share is the same thing as profits and
revenues, a second Shell Game is played because the answer then
attacks a conclusion that is similar but different than the given
conclusion.
If the conclusion were as follows:
                         GMS = gain market share in the carpet market  C = purchasing competitors
                         C ---> GMS
then answer choice (C) would be correct (again, assuming market
share is the same thing as profits and revenues). But, the above is a
Mistaken Reversal of the conclusion, and so the attack is made on a
statement that uses the same terms as the conclusion but puts them in
a different relationship. This is a great example of the cleverness
displayed by the test makers. Fortunately you can avoid this answer if
you know what to look for when attacking conditional reasoning.
More on this topic in the next section.
第二点是否可以这样理解：原文是GMS-->C，所以若加强需要其逆否命题是非C-->非GMS，削弱就需要非C-->GMS或者C-->非GMS
求各位解答，还有解释中的condition是什么类型？可否理解为要干某事就必须得干另一件事？

xiqiong

Answer choice C is chosen by nearly 2/3 of people - even though it is the wrong answer! Extraordinary! But C does not strengthen because it simply shows that merger may not lead to increased market share. But we never said that it did! We said that a merger was the only way to increase market share. It is as if I said, the GMAT is the only way to get into business school and you showed me someone who took the GMAT and did not go to business school. That happens all the time. The way to weaken would be to say that you can take the GRE and go to business school.

这是一个教员说的~ 刚好解释你的问题哈~

sophia王晗

好哒，谢谢