Last visit was: 19 Nov 2025, 02:59 It is currently 19 Nov 2025, 02:59
Close
GMAT Club Daily Prep
Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track
Your Progress

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
Close
Request Expert Reply
Confirm Cancel
User avatar
ugimba
Joined: 01 Aug 2008
Last visit: 15 Sep 2014
Posts: 329
Own Kudos:
4,922
 [22]
Given Kudos: 99
Posts: 329
Kudos: 4,922
 [22]
3
Kudos
Add Kudos
19
Bookmarks
Bookmark this Post
Most Helpful Reply
User avatar
TommyWallach
User avatar
Manhattan Prep Instructor
Joined: 21 Jan 2010
Last visit: 14 Nov 2011
Posts: 323
Own Kudos:
7,316
 [7]
Given Kudos: 11
Affiliations: ManhattanGMAT
Location: San Francisco
Concentration: Journalism
Expert
Expert reply
Posts: 323
Kudos: 7,316
 [7]
7
Kudos
Add Kudos
Bookmarks
Bookmark this Post
General Discussion
User avatar
nitya34
Joined: 04 Jan 2008
Last visit: 06 Mar 2014
Posts: 516
Own Kudos:
Given Kudos: 17
Posts: 516
Kudos: 4,361
Kudos
Add Kudos
Bookmarks
Bookmark this Post
User avatar
Economist
Joined: 01 Apr 2008
Last visit: 24 Dec 2018
Posts: 383
Own Kudos:
Given Kudos: 18
Name: Ronak Amin
Schools: IIM Lucknow (IPMX) - Class of 2014
Schools: IIM Lucknow (IPMX) - Class of 2014
Posts: 383
Kudos: 4,450
Kudos
Add Kudos
Bookmarks
Bookmark this Post
For me B. What is OA?

B because even before 1976 discharges declined, still the contamination level didnt reduce much, however only during 1975-85 major decline in contamination happened, which means there was another major cause for this decline in contamination => decline in the gasoline usage.


Not E, because E talks about the decline in the use of gasoline and not about the decilne in the lead contamination level, there doesnt seem to be any link. Also it boils down to 1985 which doest help much.


ugimba
The level of lead contamination in United States rivers declined between 1975 and 1985. Federal regulations requiring a drop in industrial discharges of lead went into effect in 1975, but the major cause of the decline was a 75 percent drop in the use of leaded gasoline between 1975 and 1985.
Which of the following, if true, best supports the claim that the major cause of the decline in the level of lead contamination in United States rives was the decline in the use of leaded gasoline?
(A) The level of lead contamination in United States rivers fell sharply in both 1975 and 1983.
(B) Most of the decline in industrial discharges of lead occurred before 1976, but the largest decline in the level of river contamination occurred between 1980 and 1985.
(C) Levels of lead contamination in rivers fell sharply in 1975-1976 and rose very slightly over the next nine years.
(D) Levels of lead contamination rose in those rivers where there was reduced river flow due to drought.
(E) Although the use of leaded gasoline declined 75 percent between 1975 and 1985, 80 percent of the decline took place in 1985.
User avatar
VerbalBot
User avatar
Non-Human User
Joined: 01 Oct 2013
Last visit: 04 Jan 2021
Posts: 18,832
Own Kudos:
Posts: 18,832
Kudos: 986
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Hello from the GMAT Club VerbalBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
Moderators:
GMAT Club Verbal Expert
7445 posts
GMAT Club Verbal Expert
234 posts
188 posts