T-3-Q21.
Driving the steep road to the mountaintop Inca ruins of Machu Picchu
is potentially dangerous and hiking there is difficult. Now the Peruvian government is installing a cable car that will make access much easier, and hence results in a large increase in tourisms. However, since the presence of large numbers of tourists tends to accelerate the deterioration of a site, installation of a cable car is certain to result in harm to the ruins.
Which of the following, if true, most seriously calls into question the argument?
A.The daily number of tourists that are expected to take the cable car to Machu Picchu
is smaller than the original resident
B.The construction of the cable car terminal at Machu Picchu
will require the use of potentially damaging heavy machinery at the site.
C.Machu Picchu
is already one of the most popular tourist sites in Peru
D.Natural weathering will continue to be a more significant cause of the deterioration of Machu Picchu
than tourist traffic
E.The cable car will replace the tour buses whose large wheels and corrosive exhaust at present do significant damage to the site.
答案是E。但是为什么D不是呢？D不是也是他因么？
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