Kaplan Coursebook Question-Experts help please.

This topic has expert replies
Master | Next Rank: 500 Posts
Posts: 120
Joined: Mon Nov 07, 2011 10:54 pm
Location: Delhi
Thanked: 5 times
A particular island off the coast of Central America has traditionally been a popular travel destination for European tourists. An official from the island's tourism authority has announced that the number of cases of intestinal distress reported by tourists fell precipitously this year compared to last year. She credits this improvement to the island's new water treatment plant.

Which of the following statements,if true, most weakens the tourism authority official's claim that the new plant has caused fewer cases of intestinal distress.

A)The new water treatment plant was designed and constructed by a french water company that has a reputation for excellence.
B)An american beverage company began selling bottled water on the island in the early 90s, and the product has been popular with European tourists.
C)All the major cruise ships lines that visit the island with European tourists keep careful records of all cases of intestinal distress and report the cases to the tourism authority.
D)A hurricane struck the island this year , causing significant damage and lowering by more than 50 percent the number of tourists visiting from Europe.
E)The new water treatment plant has been used heavily in advertisements for travel to the island.

OA after discussion.

User avatar
Legendary Member
Posts: 641
Joined: Wed Apr 20, 2011 1:15 am
Thanked: 149 times
Followed by:32 members
GMAT Score:760

by avik.ch » Thu Jan 26, 2012 1:48 am
IMO : D

User avatar
GMAT Instructor
Posts: 15539
Joined: Tue May 25, 2010 12:04 pm
Location: New York, NY
Thanked: 13060 times
Followed by:1906 members
GMAT Score:790

by GMATGuruNY » Thu Jan 26, 2012 4:13 am
bryan88 wrote:A particular island off the coast of Central America has traditionally been a popular travel destination for European tourists. An official from the island's tourism authority has announced that the number of cases of intestinal distress reported by tourists fell precipitously this year compared to last year. She credits this improvement to the island's new water treatment plant.

Which of the following statements,if true, most weakens the tourism authority official's claim that the new plant has caused fewer cases of intestinal distress.

A)The new water treatment plant was designed and constructed by a french water company that has a reputation for excellence.
B)An american beverage company began selling bottled water on the island in the early 90s, and the product has been popular with European tourists.
C)All the major cruise ships lines that visit the island with European tourists keep careful records of all cases of intestinal distress and report the cases to the tourism authority.
D)A hurricane struck the island this year , causing significant damage and lowering by more than 50 percent the number of tourists visiting from Europe.
E)The new water treatment plant has been used heavily in advertisements for travel to the island.

OA after discussion.
The premise is about X: The number of cases of intestinal distress reported by tourists fell precipitously this year.
The conclusion is about Y: The island's new water treatment plant.

To weaken the conclusion, the correct answer must BREAK THE LINK between X and Y: it must show that the new water treatment plant is NOT linked to the decrease in the NUMBER OF CASES of intestinal distress.
One way to break the link is to provide an ALTERNATE CAUSE for the decrease in the number of cases.

Answer choice D does just that: A hurricane struck the island this year, causing significant damage and lowering by more than 50 percent the number of tourists visiting from Europe. This answer choice links the DECREASE IN THE NUMBER OF TOURISTS to the DECREASE IN THE NUMBER OF CASES of intestinal distress, thereby breaking the link between the new water treatment plant and the number of cases.

The correct answer is D.

Some test-takers might be tempted by B. Whereas the argument discusses a change that took place THIS YEAR, B discusses a change that took place IN THE EARLY 90's. Thus, B is outside the scope.
Private tutor exclusively for the GMAT and GRE, with over 20 years of experience.
Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.

As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.

For more information, please email me (Mitch Hunt) at [email protected].
Student Review #1
Student Review #2
Student Review #3

Master | Next Rank: 500 Posts
Posts: 382
Joined: Thu Mar 31, 2011 5:47 pm
Thanked: 15 times

by ArunangsuSahu » Thu Jan 26, 2012 9:22 am
No Doubt about (D).. Alternate Reason

Master | Next Rank: 500 Posts
Posts: 120
Joined: Mon Nov 07, 2011 10:54 pm
Location: Delhi
Thanked: 5 times

by bryan88 » Thu Jan 26, 2012 10:23 am
Thanks Mitch.
But how are we sure when ruling out B? Where is it mentioned that 'this year' couldn't be early nineties?

User avatar
GMAT Instructor
Posts: 578
Joined: Tue Aug 25, 2009 6:00 pm
Thanked: 136 times
Followed by:62 members

by KapTeacherEli » Thu Jan 26, 2012 12:46 pm
hi Bryan,

When the GMAT says "last year," it means "last year!" Assume the text was written on the day you take the test, unless given specific reason to think otherwise.
Eli Meyer
Kaplan GMAT Teacher
Cambridge, MA
www.kaptest.com/gmat

ImageImageImage