Geologists have found that streams in the Karoo basin of Sou

Question

Geologists have found that streams in the Karoo basin of South Africa changed suddenly at the end of the Permian period 250 million years ago,  from the meandering shape typically found in well-vegetated zones to the braided pattern found in areas without deep-rooted vegetation to hold  the soil together.

(A) from the meandering shape typically found in well-vegetated zones to the braided pattern found in areas without deep-rooted vegetation to hold

(B) from the meandering shape typically found in well-vegetated zones to the braided pattern that they find in areas without deep-rooted vegetation for holding

(C) from the meandering shape typical in well-vegetated zones to the braided pattern found in areas where it is without deep-rooted vegetation for holding

(D) shifting from the meandering shape typically found in well-vegetated zones to the braided pattern found in areas where it is without deep-rooted vegetation for holding

(E) shifting from the meandering shape that is typical in well-vegetated zones to the braided pattern being found in areas without deep-rooted vegetation to hold

https://www.newscientist.com/article/mg16722563-900-wipe-out/

IN BRIEF 
 16 September 2000 
 Wipe out

TRACES of ancient river beds in the Karoo basin of South Africa show that land plants took a heavy hit during Earth’s greatest mass extinction.

At the end of the Permian period 250 million years ago, 95 per cent of species were wiped out and Europe became a desert (New Scientist, 4 December 1999, p 17). Now geologists have found that streams in the Karoo changed suddenly at the same time,  from the meandering shape typical in well-vegetated zones to the braided pattern found in areas lacking deep-rooted vegetation to hold  the soil together.

Something killed plants throughout the region, causing rapid soil erosion, Peter Ward of the University of Washington reports in Science (vol 289, p 1740). He suggests extinctions on land may have preceded those at sea, but the underlying cause remains a mystery.

kinjiGC · Accepted Answer

Geologists have found that streams in the Karoo basin of South Africa changed suddenly at the end of the Permian period 250 million years ago, from the meandering shape typically found in well-vegitated zones to the braided pattern found in areas without deep-rooted vegetation to hold the soil together.

(A) from the meandering shape typically found in well-vegetated zones to the braided pattern found in areas without deep-rooted vegetation to hold - Looks good.

(B) from the meandering shape  typically found  in well-vegetated zones to the braided pattern that  they find in areas  without deep-rooted vegetation for holding -  Parallelism issue - From X to Y. X and Y should be parallel.
 
(C) from the meandering shape typical in well-vegetated zones to the braided pattern found in areas where  it is  without deep-rooted vegetation for holding -  it is makes the option more wordy. It doesn't have an antecedent and acts as a placeholder which is not really required. - Incorrect

(D) shifting from the meandering shape typically found in well-vegetated zones to the braided pattern found in areas where  it is  without deep-rooted vegetation for holding - 
 Same issue as that of Option C)

(E) shifting from the meandering shape that is typical in well-vegetated zones to the braided pattern  being  found in areas without deep-rooted vegetation to hold -  being - Indicates that it is happening right now. incorrect.

One more thing.
I prefer drinking coffee to drinking tea  to keep  me awake at night.
I prefer drinking coffee to drinking tea  for keeping  me awake at night.

2nd option doesn't provide the intent hence  for keeping  is not the correct usage.  This is one more issue with "For holding" in Option B,C and D.

I am not sure if  shifting  is incorrect.

I changed my books orientation, shifting from bookshelf placed in my bedroom to bookshelf placed in my living room.

Shifting is verbing modifier provides more info about I changed my books.

And If I break the sentences in clauses:

Geologists have found 
 that streams in the Karoo basin of South Africa changed suddenly at the end of the Permian period 250 million years ago
 shifting from X to Y.
So the subject of the verbing modifier is still streams and shifting can be tagged to the subject and it makes sense.

I don't think "shifting" is a issue here.

maaadhu · Answer

A is the correct answer

2 points are tested in this question i.e. Idiom (From X To Y) and Parallelism

B, C, & E use the correct idiom From X to Y but violate parallelism. X & Y are not parallel.

D has modifier error. The verb-inf modifier "Shifting from ...." either has to present the result of the first statement or provide additional information about the first clause. It does neither rather explain how the transformation took place.

benguy · Answer

Geologists have found that streams in the Karoo basin of South Africa changed suddenly at the end of the Permian period 250 million years ago, from the meandering shape typically found in well-vegitated zones to the braided pattern found in areas without deep-rooted vegetation to hold the soil together.

(A) from the meandering shape typically found in well-vegetated zones to the braided pattern found in areas without deep-rooted vegetation to hold

Correct : from X to Y (parallel) ; Infinitive form "to hold' is correct

(B) from the meandering shape typically found in well-vegetated zones to the braided pattern that they find in areas without deep-rooted vegetation for holding

Change in meaning : Incorrect

(C) from the meandering shape typical in well-vegetated zones to the braided pattern found in areas where it is without deep-rooted vegetation for holding

"For holding " is In correct , "To hold" indicates purpose correctly

(D) shifting from the meandering shape typically found in well-vegetated zones to the braided pattern found in areas where it is without deep-rooted vegetation for holding

Verb -ing modifier "shifting...holding" modifies verb in preceding clause : Incorrect

(E) shifting from the meandering shape that is typical in well-vegetated zones to the braided pattern being found in areas without deep-rooted vegetation to hold

Same as D

gmatter0913 · Answer

Is there any difference in meaning among the following sentences?

Geologists have found that streams in the Karoo basin of South Africa changed suddenly at the end of the Permian period 250 million years ago, from the meandering shape typically found in well-vegitated zones to the braided pattern found in areas without deep-rooted vegetation to hold the soil together.

Geologists have found that streams in the Karoo basin of South Africa changed suddenly at the end of the Permian period 250 million years ago, shifting from the meandering shape typically found in well-vegitated zones to the braided pattern found in areas without deep-rooted vegetation to hold the soil together.

TGC · Answer

I was stumped too on this one.

Verb modifiers can be placed anywhere.

From X to Y is a verb modifier modifying 'changed suddenly' how streams changed?

PiyushK · Answer

applying POE to get the answer.

Geologists have found that streams in the Karoo basin of South Africa changed suddenly at the end of the Permian period 250 million years ago,  from the meandering shape typically found in well-vegitated zones to the braided pattern found in areas without deep-rooted vegetation to hold  the soil together.

(A) from the meandering shape typically found in well-vegetated zones to the braided pattern found in areas without deep-rooted vegetation to hold
(B) from the meandering shape typically found in well-vegetated zones to the braided pattern that they find in areas without deep-rooted vegetation  for holding 
(C) from the meandering shape  typical  in well-vegetated zones to the braided pattern found in areas where  it  is without deep-rooted vegetation for holding
(D) shifting from the meandering shape typically found in well-vegetated zones to the braided pattern found in areas where  it  is without deep-rooted vegetation for holding
(E) shifting from the meandering shape that is  typical  in well-vegetated zones to the braided pattern  being  found in areas without deep-rooted vegetation to hold

junkostem · Answer

Shifting  is incorrect because is it redundant. Change is already mentioned earlier, so that makes the addtion of shifting unnecessarily wordy.

EducationAisle · Answer

Actually this is an interesting observation. While  infinitives express intent  is generally true, did you notice that you actually used  prefer drinking  and not  prefer to drink .

When two  verbs  (or  verb forms ) appear together, the  first  verb determines whether the second verb will be in the  gerund  form (-ing form of the verb) or in the  infinitive form  (to + the basic form of the verb).

For example, let us take the word  enjoy . We would always say:

I enjoy swimming .

And not

I enjoy to swim .

p.s. This topic has been discussed in detail in our book. If you can PM me your mail id, I can send the corresponding section to you.

AdmitJA · Answer

Is there a difference between the usage of "from" and "shifting from". If option E was copy paste of option A and had the word shifting in addition, which option would be the correct answer?

pqhai · Answer

Hello joseph0alexander.

D and E are wrong because of redundancy. "shifting" is not necessary. You can look back to the non-underlined portion: ".......streams in the Karoo basin of South Africa  changed  suddenly at the end of the Permian period 250 million years ago.......,  shifting  from X to Y....."

"change" means "shift". In fact, it's a very classical trick used by GMAT. It uses a same meaning word  in the non-underlined portion , so if read too fast, we will ignore a small but important point.

Hope it helps.

BillyZ · Answer

GMATNinja   GMATNinjaTwo  Could you help to explain the different of " to hold " (A) and " for holding " (B) in this problem?

GMATNinja · Answer

Ziyuen, I don't think it's a major issue here. That particular part of the sentence describes the usefulness of the deep-rooted vegetation, and I don't think that "for holding" is necessarily wrong in this case. "To hold" is probably a little bit better, since "for holding" seems to imply some sort of specific design or intent -- and that's probably not ideal here. But I wouldn't automatically dismiss "for holding" in this particular sentence. Not coincidentally, it's a non-issue in the sentence. The GMAT gives us very clear errors (pronouns and redundancies) in the other answer choices -- so there's no real reason to even worry about the idiom. That's classic GMAT SC: distract us with a split that doesn't matter much, while the real issues lie elsewhere.

mogarza08 · Answer

wouldn't answer choice D and E be considered participle phrases since it contains the ,ing structure at the end? If so, wouldn't it modify the subject Geologists?

sambit66 · Answer

The first thing I realized after reading this sentence is that after "comma", there shud be somethng that modifies "changed suddenly" (how did it changed suddenly is the first question that i asked myself). So i started looking for somethng with "ing". So i directly went to 4th and 5th option. But i found "areas where" and "for holding" in option 4 as incorrect. So i went to option 5. Here also i didnt like "being". So i discared. I had taken for granted that when you try to modify preceding clause you should use "comma+ing" or "comma+with". I was confused. But anyhow i selected the correct ansr(which is "a"). But i didnt understand why a? So after thinking for some time I figured out that "at the end of the Permian period 250 million years ago" is just a prepositional phrase and "from" in option a can be used to modify "changed" in the previous sentence. Is my interpretation correct ? Does this sentence give us any extra takeawy (beside the one which we know that except "comma+with" all "comma+prepositions" are used to modify somethng just before the comma? Does "comma+from" in this sentence work like "comma+with" type of sentences?).

egmat · Answer

Hello mogarza08 , I am not sure whether you still have this doubt. Here are my two cents anyway. :-)

It is true that comma + shifting in Choice D and E is the comma + verb-ing modifier that modifies the preceding action. In this case, the action that precedes comma + shifting is changed . So comma + shifting modifies the action changed and hence associates with streams in the Karoo basin of South Africa , the doer of the modified action. Since the modification is logical and the modifier makes sense with the doer of the modified action, use of comma + shifting is correct in Choice D and E. Hope this helps. :-)

Thanks. Shraddha

egmat · Answer

Hello sambit66 , I will be glad to help you with this one. :-)

IMHO, your analysis is very grammar oriented and looks a little inorganic, something that you are arriving at to justify the correct answer choice. This is how I looked at the sentence. The sentence intends to say that some streams changed from X to Y to do something . Rest everything is additional information about some entity or the other. I also do not give undue importance to the usage of comma in a sentence. I did not in this one too. For me, the comma before form just presents the necessary pause in the sentence so that I can understand well what this long sentence is actually trying to convey. I only went by the context and the meaning conveyed by the original sentence. I did check for the grammatical nuances, but the very basic ones, nothing too complicated. But for me, the conveyed meaning makes it clear what the sentence is all about. That's our approach at e-GMAT. Hope this helps. :-)

Thanks. Shraddha

rishabhdxt · Answer

Geologists have found that streams in the Karoo basin of South Africa changed suddenly at the end of the Permian period 250 million years ago, from the meandering shape typically found in well-vegitated zones to the braided pattern found in areas without deep-rooted vegetation to hold the soil together.

(A) from the meandering shape typically found in well-vegetated zones to the braided pattern found in areas without deep-rooted vegetation to hold

Correct : from X to Y (parallel) ; Infinitive form "to hold' is correct

(B) from the meandering shape typically found in well-vegetated zones to the braided pattern that they find in areas without deep-rooted vegetation for holding

Change in meaning : Incorrect

(C) from the meandering shape typical in well-vegetated zones to the braided pattern found in areas where it is without deep-rooted vegetation for holding
 
"For holding " is In correct , "To hold" indicates purpose correctly

(D) shifting from the meandering shape typically found in well-vegetated zones to the braided pattern found in areas where it is without deep-rooted vegetation for holding

Verb -ing modifier "shifting...holding" modifies verb in preceding clause : Incorrect

(E) shifting from the meandering shape that is typical in well-vegetated zones to the braided pattern being found in areas without deep-rooted vegetation to hold

Same as D

rishabhdxt · Answer

Geologist have found (something) , shifting from X to Y
This seems nonsensical . 
Did geologist shift ?

Pls suggest.

rishabhdxt · Answer

Hi GMATNINJA

Do we have parallelism issue in option B

(B)  from  the meandering shape typically found in well-vegetated zones  to  the braided pattern  that they find in areas without deep-rooted vegetation for holding

pls help

Geologists have found that streams in the Karoo basin of Sou

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Geologists have found that streams in the Karoo basin of Sou

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