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
Start free 5-day trial
Read 563 reviewsTarget Test Prep

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

Assumption! Tufe Island

Expert replies
Post new topic Post Reply
Subscribe topic
Previous Topic Next Topic
Master | Next Rank: 500 Posts
Posts: 193
Joined: Wed Dec 05, 2012 6:53 amFollowed by: 5 members
Thanked: 4 times
by amysky_0205 » Sat Dec 22, 2012 9:14 pm
Two centuries ago, Tufe Peninsula became separated form the mainland, isolating on the newly formed Tufe Island a population of Turfil sunflowers. This population's descendants grow to be, on average, 40 centimeters shorter than Turfil sunflowers found on the mainland. Tufe Island is significantly drier than Tufe Peninsula was. So the current average height of Tufe's Turfil sunflowers is undoubtedly at least partially attributable to changes in Tufe's environmental conditions. Which of the following is an assumption on which the argument depends?

A. There are no types of vegetation on Tufe Island that are known to benefit from dry conditions.
B. There were about as many Turfil sunflowers on Tufe Peninsula two centuries ago as there are on Tufe Island today.
C. The mainland's environment has not changed in ways that have resulted in Turfil sunflowers on the mainland growing to be 40 centimeters taller than they did two centuries ago.
D. The soil on Tufe Island, unlike that on the mainland, lacks important nutrients that help Turfil sunflowers survive and grow tall in a dry environment.
E. The 40-centimeter height difference between the Turfil sunflowers on Tufe Island and those on the mainland is the only difference between the two populations.

OA: C

can someone explain this ?!?!?!
just can't figure it out... tks!
Top
Join the discussion
Source: — Critical Reasoning |
Master | Next Rank: 500 Posts
Posts: 142
Joined: Sat Oct 20, 2012 3:31 amFollowed by: 3 members
Location: New Delhi
Thanked: 20 times

by aman88 » Sun Dec 23, 2012 12:19 am
Evidence + assumption = conclusion.

As soon as we understand the above equation, we can graphically imagine the scope of the argument.
1)Sunflowers on Tufe island
2)Sunflowers on Tufe Mainland

The argument is describing differences in the sunflowers on island and mainland and why there is a difference.

Lets work on the argument now:

Evidence: On Tufe island - Sunflowers are 40 cms 'shorter'. Climate is 'drier'.
Conclusion: The short height of sunflowers in the Tufe Island is due to changes in the environmental conditions there.

*notice the words shorter and drier. Those words show some comparison between the sunflowers of Island and the mainland. Therefore, the climate must be less dry on the mainland and sunflowers must be 40 cms taller.

In assumption CR questions, Negation Test works well(already explained before). Lets work on the answer choices and see how negating them affects the conclusion.

A. There are some types of vegetation on Tufe Island that are known to benefit from dry conditions. -> Does not affect the conclusion in any way. ELIMINATE
B. There were fewer Turfil sunflowers on Tufe Peninsula two centuries ago as there are on Tufe Island today. -> Does not affect the conclusion in any way. ELIMINATE
C. The mainland's environment has somehow changed in ways that have resulted in Turfil sunflowers on the mainland growing to be 40 centimeters taller than they did two centuries ago. ->After negating, it seems to refute the conclusion. ANSWER
D. The soil on Tufe Island, unlike that on the mainland, contains important nutrients that help Turfil sunflowers survive and grow tall in a dry environment. -> Does not affect the conclusion in any way. ELIMINATE
E. The 40-centimeter height difference between the Turfil sunflowers on Tufe Island and those on the mainland may not be the only difference between the two populations. -> Does not affect the conclusion in any way. ELIMINATE

Understand the basic equation of assumption CR questions. That's it.
Therefore, C.

Thanks.
Top
Join the discussion