BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem

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.

★★★★★5.0563 reviews
Newsweek Readers’ Choice Awards 2026 winner: Target Test Prep, #1 Test Prep
NEWSWEEK READERS’ CHOICE AWARDS 2026

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

GMATLiveTeach Starts Oct 17
Chris Peckover, Target Test Prep GMAT expert
LIVE ONLINE CLASSES

Get Ready for GMAT Test Day Faster with Live Online Classes

with Chris Peckover, 100th-Percentile GMAT Scorer

Oct 17 · Chris Peckover
Sat · 11:00 AM to 2:00 PM ET
Oct 20 · Chris Peckover
Tue, Thu · 8:00 to 10:00 PM ET
Oct 25 · Josh Braslow
Sun · 1:00 to 4:00 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
EALiveTeachOnDemand 5 seats left Start anytime
EXECUTIVE ASSESSMENT

Target Test Prep EA OnDemand

Self-paced EA prep. Study on your schedule.

Logan Thompson
EXECUTIVE ASSESSMENT

Sep 6 to Dec 6, 2026

with Logan Thompson

165+ EA score guarantee
$05-day trial no automatic billing
Schedule
Sun · 9:30 AM to 12:30 PM ET
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
GMATOnDemand Start 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

Compare the format, schedule, and included access before enrolling. Prices and seat counts shown reflect the supplied offer details.

CR TC 55 3

Expert replies
by SmarpanGamt » Tue Nov 09, 2010 12:46 pm
Dutch elm disease, which is caused by the fungus C. ulmi spread by adult scolytid beetles, has already destroyed 70 percent of the elms in Greenwood Forest. Another naturally occurring fungus, P. oblonga, kills larvae of the scolytid beetle. Forest rangers plan to introduce P. oblonga into Greenwood Forest in order to save the remaining mature elms.

Which of the following, if true, would cast the most serious doubt on the plan's prospects for success?

(A) During the last year, the scolytid beetle population in Greenwood Forest has decreased by 30 percent because of cold-weather conditions.
(B) Dutch elm disease cannot be abated by introducing chemical compounds used to arrest the diseases of many other species of tree.
(C) Introduction of P. oblonga saved elm trees in neighboring Gatemar and Lavemont forests.
(D) For P. oblonga to control scolytid beetles successfully, it must be established in a forest prior to the beetle infestation.
(E) Greenwood Forest has lost many maple trees because of a fungus infection

Please explain your choice OA later
Join the discussion
Source: — Critical Reasoning |

by Ravish » Tue Nov 09, 2010 1:19 pm
My pick is (D)

If the P. oblonga fungus is only effective if introduced prior to a beetle infestation, then introducing the fungus in the greenwood forest would not serve any purpose as Greenwood, as the question states, is already suffering from a beetle infestation.
Join the discussion

by SmarpanGamt » Tue Nov 09, 2010 1:33 pm
OK then lets look the option "D" as

D : For P. oblonga to control scolytid beetles successfully, it must be established in a forest prior to the beetle infestation

If the option was : P. oblonga is not established in the control scolytid beetles successfully. ( Then the option would weaken the point)


what if establish
Since the option opens in two folds ( If established and If not established) chosing this one was tricky. the option provides a step prior to the weakening point. however, option was a contenter for me but not the answer.
OA is D
Join the discussion

by RikaMueller » Sun Nov 21, 2010 3:56 am
so which one is the correct answer? B?
Join the discussion