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.

答案选的是e，但我觉得a也有道理啊。原文说大量游客会损坏景点，a中说有了car之后每天乘坐car的游客反而比以前少，因此能削弱原文。这样子想有道理么？