Live GMAT classes with Target Test Prep start Nov 21 and Nov 22. First class free.

See classes
Target Test Prep · GMAT

Choose how you want to prepare

Learn live with an expert or move at your own pace. Every option includes the complete TTP study system.

Newsweek Readers’ Choice Awards 2026 winner: Target Test Prep, #1 Test Prep

Target Test Prep was voted #1 Best Test Prep in the 2026 Newsweek Readers’ Choice™ Awards.

★★★★★5.0563 reviews
GMATLiveTeachStarts Nov 22
Josh Braslow, Target Test Prep GMAT expert
LIVE ONLINE CLASSES

Get Ready for GMAT Test Day Faster with Live Online Classes

with Josh Braslow, 20+ years in test prep

Nov 22 · Josh Braslow
Sun · 9:30 AM to 12:30 PM ET
Included
40 hours of live online classes + 6 months of TTP OnDemand
  • Attend the first class for free
  • Every class is recorded, so you never fall behind
View classes & enroll
Limited seats availableTarget Test Prep
EALiveTeachOnDemandStart anytime
EXECUTIVE ASSESSMENT

Target Test Prep EA OnDemand

Self-paced EA prep. Study on your schedule.

EXECUTIVE ASSESSMENT

with

165+ EA score guarantee
$05-day trial no automatic billing
Schedule
Included
40 hours of live online classes plus six months of access to the complete TTP EA OnDemand course.
  • 165+ EA Score Guarantee
  • 4,100+ Quant, Verbal, and Integrated Reasoning practice questions
  • 400+ hours of in-depth video lessons
  • 3,000+ step-by-step video solutions
View EA class & enroll Start free 5-day trial
Limited cohort · enrollment openTrial includes full course accessTarget Test Prep
GMATOnDemandStart anytime
SELF-PACED MASTERCLASS

Target Test Prep GMAT OnDemand

Complete access from day one. Study on your schedule.

715+ score guarantee
$0to start then $127/mo
  • Personalized study plan and analytics
  • Thousands of lessons and practice questions

oceanographers' hypothesis

Expert replies
by success1111 » Sun Apr 26, 2009 11:08 pm
Plankton generally thrive in areas of the ocean with sufficient concentrations of certain nitrogen compounds near the surface,where plankton live. Nevertheless,some areas, though rich in these nitrogen compounds,have few plankton. These areas have particularly low concentrations of iron,and oceanographers hypothesize that this shortage of iron prevents plankton from thriving. However,an experimental release of iron compounds into one such area failed to produce a thriving plankton population,even though local iron concentrations increased immediately.


Which of the following,if true,argues against concluding,on the basis of information above,that the oceanographers' hypothesis is false?


a) Not all of the nitrogen compounds that are sometimes found in relatively high concentrations in the oceans are nutrients for plankton.

b) Certain areas of the ocean support n abundance of plankton despite having particularly low concentration of iron.

c) The release of the iron compounds did not increase the supply of nitrogen compounds in the area.

d) A few days after the iron compounds were released,ocean currents displayed the iron-rich water from the surface.

e) The iron compounds released into the area occur naturally in areas of the ocean where plankton thrive.
Trust but verify.
Join the discussion
Source: — Critical Reasoning |

by ketkoag » Mon Apr 27, 2009 12:37 am
IMO C.
whats the OA??
nice question, source please..
Join the discussion

by piyush_nitt » Mon Apr 27, 2009 5:17 pm
ketkoag wrote:IMO C.
whats the OA??
nice question, source please..
IMO E

Planktons are the cause of iron, not vice versa.
Join the discussion

by cramya » Mon Apr 27, 2009 5:31 pm
Guys,
I have seen this question on the gmatclub forum and in the 4th choice a word is misspelled which is essential to arriving at the answer.

d) A few days after the iron compounds were released,ocean currents displayed the iron-rich water from the surface.


The word above in bold must be "displaced" leading to OA: D


Please ensure when posting the question the question and the answer choices are as is. It may be an unintentional mistake but nevertheless throws the readers off.


Link for the correct question and answer choices:

https://gmatclub.com/forum/cr-plankton-70844.html

Regards,
CR
Join the discussion

by success1111 » Mon Apr 27, 2009 9:45 pm
cramya wrote:Guys,
I have seen this question on the gmatclub forum and in the 4th choice a word is misspelled which is essential to arriving at the answer.

d) A few days after the iron compounds were released,ocean currents displayed the iron-rich water from the surface.


The word above in bold must be "displaced" leading to OA: D


Please ensure when posting the question the question and the answer choices are as is. It may be an unintentional mistake but nevertheless throws the readers off.


Link for the correct question and answer choices:

https://gmatclub.com/forum/cr-plankton-70844.html

Regards,
CR
Yeah.Apology for the topo here.And thanks everyone.
I have using GMAT-based questions to practise and i can mistake in typing like everyone else.And sometimes,auto-dictionary software can throw one off balance.
By the way, OA is D.
Trust but verify.
Join the discussion

by ashley.com » Sun May 15, 2016 3:47 am
I am leaning more towards C
Join the discussion