Guide 6, page 123

[mneeti]

SC-Guide 6, Page 123

In 2001 the Peruvian government began requiring tourists to buy expensive permits to hike the remote Inca Trail, which goes to the ancient city of Machu Picchu, The total number of permits is strictly limited; infact, only 500 people per day are now allowed to hike the Inca Trail, whereas before 2001 daily visitors numbered in the thousands. The Peruvian government claims that this permit program has successfully prevented deterioration of archaeological treasures along the Inca Trail.

Which of the following, if true, most strengthens the argument above?

(A)Since 2001, tourist guides along the Inca Trail have received 50% to 100% increases in take-home pay.

(B)Villages near Machu Picchu have experienced declines in income, as fewer tourists buy fewer craft goods and refreshments.

(C)Many of the funds from the sale of Inca Trail permits are used to staff a museum of Incan culture in Lima, Peru's capital, and to hire guards for archaeological sites without permit programs.

(D)Since 2001, Incan ruins similar to Machu Picchu but not on the Inca Trail have disintegrated at a significantly greater rate than those on the Inca Trail.

(E)The total number of tourists in Peru has risen substantially since 2001, even as the number of tourists hiking the Inca Trail has remained constant.

My query:

Though I get that the correct answer is (D), I am confused with the wording. I do not get the meaning of Incan ruins similar to Machu Picchu but not on the Inca Trail.
If I read (D) without the words "but not on the Inca Trail", I comprehend it better.

Please explain what I am missing out in it?

Thanks!

[tim]

[please note - this question comes from the CR book, not SC, and it can be found in the 4th edition of the book]

"but not on the Inca trail" is absolutely necessary to set up the contrast between ruins on the trail and not on the trail. The answer choice actually should NOT make sense without that phrase..