Some scientists believe that 65 million years ago an : GMAT Critical Reasoning (CR)
Check GMAT Club Decision Tracker for the Latest School Decision Releases https://gmatclub.com/AppTrack

 It is currently 01 Mar 2017, 12:09

### 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

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

# Events & Promotions

###### Events & Promotions in June
Open Detailed Calendar

# Some scientists believe that 65 million years ago an

Author Message
TAGS:

### Hide Tags

SVP
Joined: 16 Jul 2009
Posts: 1628
Schools: CBS
WE 1: 4 years (Consulting)
Followers: 43

Kudos [?]: 1092 [1] , given: 2

Some scientists believe that 65 million years ago an [#permalink]

### Show Tags

27 Sep 2009, 10:14
1
KUDOS
3
This post was
BOOKMARKED
00:00

Difficulty:

(N/A)

Question Stats:

70% (02:52) correct 30% (01:53) wrong based on 149 sessions

### HideShow timer Statistics

Some scientists believe that 65 million years ago an asteroid struck what is now the Yucatan Peninsula, thereby causing extinction of the dinosaurs. These scientists have established that such a strike could have hurled enough debris into the atmosphere to block sunlight and cool the atmosphere. Without adequate sunlight, food sources for herbivorous dinosaurs would have disappeared, and no dinosaurs could have survived a prolonged period of low temperatures. These same scientists, however, have also established that most debris launched by the asteroid would have settled to the ground within six months, too soon for the plants to disappear or the dinosaurs to freeze.
Which one of the following, if true, most helps to resolve the apparent discrepancy between the scientists’ beliefs and the scientists’ results, as described above?
(A) Loss of the herbivorous dinosaurs would have deprived the carnivorous dinosaurs of their food source.
(B) Dinosaurs inhabited most landmasses on the planet but were not especially abundant in the area of the asteroid strike.
(C) A cloud of debris capable of diminishing sunlight by 20 percent would have cooled the earth’s surface by 7 to 10 degrees Celsius.
(D) The asteroid was at least 9.6 km in diameter, large enough for many dinosaurs to be killed by the strike itself and by subsequent tidal waves.
(E) Dinosaurs were susceptible to fatal respiratory problems cause by contamination of the air by asteroid debris.
_________________

The sky is the limit
800 is the limit

GMAT Club Premium Membership - big benefits and savings

If you have any questions
New!
Manager
Joined: 01 Jul 2009
Posts: 235
Followers: 3

Kudos [?]: 23 [1] , given: 39

### Show Tags

27 Sep 2009, 10:22
1
KUDOS
noboru wrote:
Some scientists believe that 65 million years ago an asteroid struck what is now the Yucatan Peninsula, thereby causing extinction of the dinosaurs. These scientists have established that such a strike could have hurled enough debris into the atmosphere to block sunlight and cool the atmosphere. Without adequate sunlight, food sources for herbivorous dinosaurs would have disappeared, and no dinosaurs could have survived a prolonged period of low temperatures. These same scientists, however, have also established that most debris launched by the asteroid would have settled to the ground within six months, too soon for the plants to disappear or the dinosaurs to freeze.
Which one of the following, if true, most helps to resolve the apparent discrepancy between the scientists’ beliefs and the scientists’ results, as described above?
(A) Loss of the herbivorous dinosaurs would have deprived the carnivorous dinosaurs of their food source.
(B) Dinosaurs inhabited most landmasses on the planet but were not especially abundant in the area of the asteroid strike.
(C) A cloud of debris capable of diminishing sunlight by 20 percent would have cooled the earth’s surface by 7 to 10 degrees Celsius.
(D) The asteroid was at least 9.6 km in diameter, large enough for many dinosaurs to be killed by the strike itself and by subsequent tidal waves.
(E) Dinosaurs were susceptible to fatal respiratory problems cause by contamination of the air by asteroid debris.

I think A, B, and D are irrelevant.

Since the passage claims that 6 months was enough to freeze the dinosaurs and kill plants I drop C as well. E seems the right answer, since dinosaurs with respiratory problems could've easily died of contamination. And maybe the CO2 levels in the atmosphere were affected as well, killing the plants on the earth. (This last one is an assumption though.)

So, IMO E.
_________________

Consider giving Kudos if you like the post.

SVP
Joined: 16 Jul 2009
Posts: 1628
Schools: CBS
WE 1: 4 years (Consulting)
Followers: 43

Kudos [?]: 1092 [0], given: 2

### Show Tags

27 Sep 2009, 10:36
arammug wrote:
noboru wrote:
Some scientists believe that 65 million years ago an asteroid struck what is now the Yucatan Peninsula, thereby causing extinction of the dinosaurs. These scientists have established that such a strike could have hurled enough debris into the atmosphere to block sunlight and cool the atmosphere. Without adequate sunlight, food sources for herbivorous dinosaurs would have disappeared, and no dinosaurs could have survived a prolonged period of low temperatures. These same scientists, however, have also established that most debris launched by the asteroid would have settled to the ground within six months, too soon for the plants to disappear or the dinosaurs to freeze.
Which one of the following, if true, most helps to resolve the apparent discrepancy between the scientists’ beliefs and the scientists’ results, as described above?
(A) Loss of the herbivorous dinosaurs would have deprived the carnivorous dinosaurs of their food source.
(B) Dinosaurs inhabited most landmasses on the planet but were not especially abundant in the area of the asteroid strike.
(C) A cloud of debris capable of diminishing sunlight by 20 percent would have cooled the earth’s surface by 7 to 10 degrees Celsius.
(D) The asteroid was at least 9.6 km in diameter, large enough for many dinosaurs to be killed by the strike itself and by subsequent tidal waves.
(E) Dinosaurs were susceptible to fatal respiratory problems cause by contamination of the air by asteroid debris.

I think A, B, and D are irrelevant.

Since the passage claims that 6 months was enough to freeze the dinosaurs and kill plants I drop C as well. E seems the right answer, since dinosaurs with respiratory problems could've easily died of contamination. And maybe the CO2 levels in the atmosphere were affected as well, killing the plants on the earth. (This last one is an assumption though.)

So, IMO E.

Could u explain bit further why you see D irrelevant?
Thanks
_________________

The sky is the limit
800 is the limit

GMAT Club Premium Membership - big benefits and savings

Manager
Joined: 14 Dec 2008
Posts: 169
Followers: 1

Kudos [?]: 24 [0], given: 39

### Show Tags

27 Sep 2009, 10:38
my ans = D
Manager
Joined: 24 Sep 2009
Posts: 111
Followers: 1

Kudos [?]: 17 [0], given: 2

### Show Tags

27 Sep 2009, 19:40
Very confused between A and E, but I'll go with A because this is the only one resolve the paradox.
Even though the dinosaurs didn't die due to freeze (because debris settled down soon), but herbivorous dinosaurs all died because lack of sunlight lead to lack of food sources, according to A, loss of the herbivorous dinosaurs would affect the food source of the carnivorous dinosaurs.
_________________

http://www.online-stopwatch.com/
http://gmatsentencecorrection.blogspot.com/

Manager
Joined: 08 Nov 2005
Posts: 182
Followers: 2

Kudos [?]: 20 [0], given: 10

### Show Tags

27 Sep 2009, 21:17
IMO D
Whats OA?
Intern
Joined: 26 Jul 2009
Posts: 17
Followers: 0

Kudos [?]: 7 [1] , given: 8

### Show Tags

28 Sep 2009, 01:44
1
KUDOS
noboru wrote:
arammug wrote:
noboru wrote:
Some scientists believe that 65 million years ago an asteroid struck what is now the Yucatan Peninsula, thereby causing extinction of the dinosaurs. These scientists have established that such a strike could have hurled enough debris into the atmosphere to block sunlight and cool the atmosphere. Without adequate sunlight, food sources for herbivorous dinosaurs would have disappeared, and no dinosaurs could have survived a prolonged period of low temperatures. These same scientists, however, have also established that most debris launched by the asteroid would have settled to the ground within six months, too soon for the plants to disappear or the dinosaurs to freeze.
Which one of the following, if true, most helps to resolve the apparent discrepancy between the scientists’ beliefs and the scientists’ results, as described above?
(A) Loss of the herbivorous dinosaurs would have deprived the carnivorous dinosaurs of their food source.
(B) Dinosaurs inhabited most landmasses on the planet but were not especially abundant in the area of the asteroid strike.
(C) A cloud of debris capable of diminishing sunlight by 20 percent would have cooled the earth’s surface by 7 to 10 degrees Celsius.
(D) The asteroid was at least 9.6 km in diameter, large enough for many dinosaurs to be killed by the strike itself and by subsequent tidal waves.
(E) Dinosaurs were susceptible to fatal respiratory problems cause by contamination of the air by asteroid debris.

I think A, B, and D are irrelevant.

Since the passage claims that 6 months was enough to freeze the dinosaurs and kill plants I drop C as well. E seems the right answer, since dinosaurs with respiratory problems could've easily died of contamination. And maybe the CO2 levels in the atmosphere were affected as well, killing the plants on the earth. (This last one is an assumption though.)

So, IMO E.

Could u explain bit further why you see D irrelevant?
Thanks

A is irrelevant because no where it is mentioned that food resources were diminished after the strike..
D is irrelevant becoz ....it only talks about many not all dinosaurs ...
E resolves the discrepancy very well...
Manager
Joined: 28 Jul 2009
Posts: 154
Followers: 3

Kudos [?]: 184 [0], given: 4

### Show Tags

28 Sep 2009, 03:00
One more for E.

After event in D some could survive breed.
Manager
Joined: 31 Aug 2009
Posts: 58
Followers: 0

Kudos [?]: 43 [0], given: 0

### Show Tags

28 Sep 2009, 03:24
C or D.

I go with C. I think D offers an alternative reason to extinction, why extinction occurred despite debris settling quickly. I think the correct answer should link the debris with the process of extinction. C does so. That's my GUESS.
Intern
Joined: 01 Sep 2009
Posts: 34
Followers: 0

Kudos [?]: 7 [1] , given: 4

### Show Tags

28 Sep 2009, 05:52
1
KUDOS
E... it gives a reason why the dinosaurs could have been killed off without depending on temperature or starvation. But also explains this would have been caused by the asteroid.. supporting the original claim
Senior Manager
Joined: 17 Jul 2009
Posts: 299
Concentration: Nonprofit, Strategy
GPA: 3.42
WE: Engineering (Computer Hardware)
Followers: 1

Kudos [?]: 41 [0], given: 9

### Show Tags

28 Sep 2009, 16:55
agree with E, D talks about most but not all dinosaurs...most dinosaur dying does not equal to extinction..
Senior Manager
Status: Yeah well whatever.
Joined: 18 Sep 2009
Posts: 345
Location: United States
GMAT 1: 660 Q42 V39
GMAT 2: 730 Q48 V42
GPA: 3.49
WE: Analyst (Insurance)
Followers: 5

Kudos [?]: 72 [0], given: 17

### Show Tags

28 Sep 2009, 18:47
E.... It's the only one that provides an alternative consequence of the asteroid that would have killed off all the dinosaurs in the short time (you can't hold your breath that long).
_________________

He that is in me > he that is in the world. - source 1 John 4:4

Manager
Joined: 21 May 2009
Posts: 142
Followers: 2

Kudos [?]: 35 [0], given: 50

### Show Tags

28 Sep 2009, 21:23
Even i would go with E
E is convincing than the rest of them
Manager
Joined: 10 Jul 2009
Posts: 129
Location: Ukraine, Kyiv
Followers: 4

Kudos [?]: 146 [1] , given: 60

### Show Tags

27 Oct 2009, 12:24
1
KUDOS
noboru wrote:
Some scientists believe that 65 million years ago an asteroid struck what is now the Yucatan Peninsula, thereby causing extinction of the dinosaurs. These scientists have established that such a strike could have hurled enough debris into the atmosphere to block sunlight and cool the atmosphere. Without adequate sunlight, food sources for herbivorous dinosaurs would have disappeared, and no dinosaurs could have survived a prolonged period of low temperatures. These same scientists, however, have also established that most debris launched by the asteroid would have settled to the ground within six months, too soon for the plants to disappear or the dinosaurs to freeze.
Which one of the following, if true, most helps to resolve the apparent discrepancy between the scientists’ beliefs and the scientists’ results, as described above?
(A) Loss of the herbivorous dinosaurs would have deprived the carnivorous dinosaurs of their food source.
We are talking here about fast cause of extinction. I believe there must be a longer period of time (>6months) in order all carnivorous dinos to kill herbivorous ones.
(B) Dinosaurs inhabited most landmasses on the planet but were not especially abundant in the area of the asteroid strike.completely irrelevant.
(C) A cloud of debris capable of diminishing sunlight by 20 percent would have cooled the earth’s surface by 7 to 10 degrees Celsius.this choice states concrete facts about the freezing processes. we do not need that.
(D) The asteroid was at least 9.6 km in diameter, large enough for many dinosaurs to be killed by the strike itself and by subsequent tidal waves.ok, D. very popular choice here. However, it presents an evidence about the size of the asteroid and its consequences. In the argument there is an information about debris and/or freezing, not tidal waves or the size of an asteroid. In addition, it is stated that 6 months is a short period for plants to disappear. If there were waves - where were the plants then?
(E) Dinosaurs were susceptible to fatal respiratory problems cause by contamination of the air by asteroid debris. best choice. in the scope of the argument and provides an alternative reason why plants survived and dinos did not.

E.

critics welcomed.
_________________

Never, never, never give up

Senior Manager
Joined: 16 Apr 2009
Posts: 339
Followers: 1

Kudos [?]: 125 [0], given: 14

### Show Tags

27 Oct 2009, 16:58
E clearly resolves the paradox . explanations already provided in greater length
_________________

Intern
Joined: 04 Oct 2009
Posts: 2
Followers: 0

Kudos [?]: 0 [0], given: 0

### Show Tags

27 Oct 2009, 18:23
IMO E,

This option properly resolve the paradox
Manager
Joined: 08 Oct 2009
Posts: 71
Location: Denmark, Europe
Schools: Darden Class of 2012
Followers: 2

Kudos [?]: 26 [0], given: 6

### Show Tags

27 Oct 2009, 22:02
noboru wrote:
Some scientists believe that 65 million years ago an asteroid struck what is now the Yucatan Peninsula, thereby causing extinction of the dinosaurs. These scientists have established that such a strike could have hurled enough debris into the atmosphere to block sunlight and cool the atmosphere. Without adequate sunlight, food sources for herbivorous dinosaurs would have disappeared, and no dinosaurs could have survived a prolonged period of low temperatures. These same scientists, however, have also established that most debris launched by the asteroid would have settled to the ground within six months, too soon for the plants to disappear or the dinosaurs to freeze.
Which one of the following, if true, most helps to resolve the apparent discrepancy between the scientists’ beliefs and the scientists’ results, as described above?
(A) Loss of the herbivorous dinosaurs would have deprived the carnivorous dinosaurs of their food source.
(B) Dinosaurs inhabited most landmasses on the planet but were not especially abundant in the area of the asteroid strike.
(C) A cloud of debris capable of diminishing sunlight by 20 percent would have cooled the earth’s surface by 7 to 10 degrees Celsius.
(D) The asteroid was at least 9.6 km in diameter, large enough for many dinosaurs to be killed by the strike itself and by subsequent tidal waves.
(E) Dinosaurs were susceptible to fatal respiratory problems cause by contamination of the air by asteroid debris.

Its E.

A assumes that the herbivorous dinosaurs became extinct. Yet we are told in the Q that the debris settled before plants died an thus there is no basis for concluding that the herbivorous dinosaurs became extinct.

B is completely irrelevant as is C.

D as others have mentioned the key-word here is many. The death of many dinosaurs is NOT equal to the extinction of dinosaurs.

E:This sentence explains why dinosaurs died from the impact even though the plants did not die and it wasn't cold enough for them to freeze to death. Therefore it solves the paradox.
Senior Manager
Joined: 12 Oct 2009
Posts: 268
Followers: 5

Kudos [?]: 159 [0], given: 4

### Show Tags

27 Oct 2009, 22:23
IMO E
"Many" is a keyword to negate option D
Intern
Joined: 20 Oct 2009
Posts: 11
Followers: 0

Kudos [?]: 0 [0], given: 0

### Show Tags

28 Oct 2009, 06:19
Seems to be clearly E.

I've been wrong before tho
Intern
Joined: 29 Jul 2009
Posts: 16
Followers: 0

Kudos [?]: 31 [0], given: 0

### Show Tags

02 Nov 2009, 22:35
I'd go with E too!
Re: dinosaurs   [#permalink] 02 Nov 2009, 22:35

Go to page    1   2    Next  [ 29 posts ]

Similar topics Replies Last post
Similar
Topics:
7 About two million years ago, lava dammed up a river in western Asia 6 18 Dec 2015, 01:29
5 For years, Scientists have believed that a certain hormone 9 25 Apr 2013, 06:06
31 Paleontologist: About 2.8 million years ago, many species 15 29 Dec 2012, 00:09
11 Years ago, some in the government's intelligence community 6 06 Nov 2012, 18:13
11 Some scientists believe that sugar causes a specific type of 14 07 May 2012, 05:48
Display posts from previous: Sort by