As part of an international effort to address environmental problems

Question

As part of an international effort to address environmental problems resulting from agricultural overproduction, hundreds of thousands of acres of surplus farmland throughout Europe will be taken out of production in coming years. Restoring a natural balance of flora to this land will be difficult, however, because the nutrients in soil that has been in constant agricultural use are depleted. Moreover, much of this land has been heavily fertilized, and when such land is left unplanted, problem weeds like thistles often proliferate, preventing many native plants from establishing themselves. While the quickest way to restore heavily fertilized land is to remove and replace the topsoil, this is impractical on a large scale such as that of the European effort. And while it is generally believed that  damaged ecological systems will restore themselves very gradually over time , a study underway in the Netherlands is investigating the possibility of artificially accelerating the processes through which nature slowly reestablishes plant diversity on previously farmed land.

In the study, a former cornfield was raked to get rid of cornstalks and weeds, then divided into 20 plots of roughly equal size. Control plots were replanted with corn or sown with nothing at all. The remaining plots were divided into two groups: plots in one group were sown with a mixture of native grasses and herbs; those in the other group received the same mixture of grasses and herbs together with clover and toadflax. After three years, thistles have been forced out of the plots where the broadest variety of species was sown and have also disappeared from mats of grass in the plots sown with fewer seed varieties. On the control plots that were left untouched, thistles have become dominant.

On some of the plots sown with seeds of native plant species, soil from nearby land that had been taken out of production 20 years earlier was scattered to see what effect introducing nematodes, fungi, and other beneficial microorganisms associated with later stages of natural soil development might have on the process of native plant repopulation. The seeds sown on these enriched plots have fared better than seeds sown on the unenriched plots, but still not as well as those growing naturally on the nearby land. Researchers have concluded that this is because fields farmed for many years are overrun with  aggressive disease organisms,  while, for example, beneficial mycorrhiza— fungi that live symbiotically on plant roots and strengthen them against the effects of disease organisms—are lacking. These preliminary results suggest that restoring natural plant diversity to overfarmed land hinges on restoring a natural balance of microorganisms in the soil. In other words, diversity underground fosters diversity aboveground. Researchers now believe that both kinds of diversity can be restored more quickly to damaged land if beneficial microorganisms are “sown” systematically into the soil along with a wide variety of native plant seeds.   1 
 1. Which one of the following most accurately expresses the central idea of the passage?

(A) The rehabilitation of land damaged by agricultural overproduction can be accelerated by means of a two-pronged strategy aimed at restoring biological diversity.
(B) Restoring plant diversity to overused farmland requires many years and considerable effort.
(C) The damaging effects of long-term agricultural overproduction argue for the modification of current agricultural practices.
(D) Soil on farmland damaged by overproduction will gradually replenish and restore itself over time if left untouched.
(E) Agricultural overproduction tends to encourage the proliferation of disease organisms in the soil as well as problem weeds.

2 
 2. Which one of the following most accurately describes the organization of the passage?

(A) A study is described, the results of the study are scrutinized, and the results are judged to be inconclusive but promising.
(B) A hypothesis is presented, evidence both supporting and undermining the hypothesis is given, and a modification of the hypothesis is argued for.
(C) A study is evaluated, a plan of action based on the study’s findings is suggested, and conclusions are drawn concerning the likely effectiveness of the plan.
(D) A goal is stated, studies are discussed that argue for modifying the goal’s objectives, and a methodology is detailed to achieve the revised goal.
(E) A problem is presented, a study addressing the problem is described, and a course of action based on the study’s findings is given.

3 
 3. The passage offers which one of the following as an explanation for why native plant varieties grew better when sown on land that had been out of production for 20 years than when sown on the plots enriched with soil taken from that land?

(A) Land that has been farmed for many years lacks certain key nutrients.
(B) Land that has been farmed for many years is usually overrun with harmful and aggressive organisms.
(C) Land that has been farmed for many years has usually been subjected to overfertilization.
(D) The soil that was taken from the land that had been out of production was lacking in fungi and other beneficial organisms.
(E) The soil that was taken from the land that had been out of production contained harmful organisms that attack plant roots.

4 
 4. Based on the passage, which one of the following is most likely to be true of any soil used to replace topsoil in the process mentioned in the first paragraph?

(A) Thistles cannot grow in it.
(B) It does not contain significant amounts of fungi.
(C) It contains very few seeds of native grasses and herbs.
(D) It does not contain large amounts of fertilizer.
(E) It was never used for growing corn or other commercial crops.

5 
 5. The author’s reference to the belief that “damaged ecological systems will restore themselves very gradually over time” ( Highlighted ) primarily serves to

(A) introduce a long-held belief that the Netherlands study is attempting to discredit
(B) cite the justification generally used by people favoring intense agricultural production
(C) suggest that the consequences of agricultural overproduction are not as dire as people generally believe
(D) present the most common perception of why agricultural overproduction is problematic
(E) describe the circumstances surrounding and motivating the Netherlands study

6 
 6. In which one of the following circumstances would it be LEAST advantageous to use the methods researched in the Netherlands study in order to restore to its natural state a field that has been in constant agricultural use?

(A) The field’s natural nutrients have been depleted through overproduction.
(B) The field’s topsoil can easily be removed and replaced.
(C) The field has been heavily fertilized for many decades.
(D) The field has the potential to support commercial grass plants such as rye.
(E) The field is adjacent to other fields where corn is growing and will continue to be grown.

7 
 7. It can be inferred from the passage that if the disease organisms mentioned in  highlighted text  were eliminated in a plot of land that had been in constant agricultural use, which one of the following would be the most likely to occur?

(A) Populations of symbiotic mycorrhiza that live in the soil would initially decline.
(B) Unwanted plant species like thistles would be unable to survive.
(C) The chance of survival of a beneficial native plant would increase.
(D) The number of all types of beneficial microorganisms would increase in the long term.
(E) Populations of other types of disease organisms would increase proportionally.

8 
 8. Which one of the following is most analogous to the process, described in the last paragraph, by which the spread of thistles can be curtailed?

(A) A newspaper works to prevent Party A from winning a majority of seats in the legislature by publishing editorials encouraging that party’s supporters to switch their allegiance and vote for candidates from a rival party.
(B) A newspaper works to prevent Party A from winning a majority of seats in the legislature by publishing editorials defending candidates from a rival party against attacks by certain broadcast journalists.
(C) A newspaper works to prevent Party A from winning a majority of seats in the legislature by publishing editorials intended to discourage supporters of Party A from voting in the upcoming election.
(D) A newspaper works to prevent Party A from winning a majority of seats in the legislature by publishing editorials attacking certain public figures who support candidates from Party A.
(E) A newspaper works to prevent Party A from winning a majority of seats in the legislature by publishing editorials intended to create antagonism between two factions within that party.

Sajjad1994 · Answer

Explanation

3. The passage offers which one of the following as an explanation for why native plant varieties grew better when sown on land that had been out of production for 20 years than when sown on the plots enriched with soil taken from that land?

Explanation

The correct answer choice is (B)

This choice requires a specific piece of information: the author’s explanation, presented beginning on  line 35 , for why native species of plants grew better when growing naturally on nearby land then when growing in plots enriched from soil nearby. Researchers, the author provides, concluded that this was attributable to the fact that overfarmed lands are overrun with aggressive disease organisms while lacking beneficial microorganisms.

Answer choice (A):  The issue is not a lack in key nutrients, so this choice can be eliminated from contention.

Answer choice (B):  This is the correct answer choice. As discussed, the researchers concluded that such land is usually overrun with aggressive disease organisms.

Answer choice (C):  Overfertilization is not the issue that is presented to explain the results specified in the question.

Answer choice (D):  This clever choice was popular among test takers; overfarmed land is overrun with disease and lacking beneficial microorganisms. The soil that was taken from the out-ofproduction land may have had some such microorganisms, although the plots to which the soil was taken may have been lacking.

Answer choice (E):  The harmful organisms were concluded to be present in the overfarmed land, not in the land that had been taken out of production.

Explanation credit: PowerScore

6. In which one of the following circumstances would it be LEAST advantageous to use the methods researched in the Netherlands study in order to restore to its natural state a field that has been in constant agricultural use?

Explanation

The correct answer choice is (B)

This question asks for the circumstances in which it would be LEAST advantageous to use the methods researched in the Netherlands study. This means that the four incorrect answer choices will provide circumstances under which the Netherlands study methods would be beneficial, and the correct answer choice will be the only exception.

Answer choice (A):  The research in the Netherlands dealt with over-farmed land, so in this circumstance the methods researched would be beneficial.

Answer choice (B):  This is the correct answer choice. If the topsoil can easily be removed and replaced, then taking that approach would be the quickest way, according to the first paragraph of the passage.

Answer choice (C):  One of the issues with over-farmed land is over-fertilization, an issue with the former cornfield studied in the Netherlands, so the methods researched in that study would be likely to be beneficial in this circumstance.

Answer choice (D):  The planting of various grass and herb species is one of the methods researched in the study, so this choice presents a circumstance under which the use of such methods would be likely to be beneficial, so this is one of the incorrect answers to this Must be True EXCEPT question.

Answer choice (E):  The passage provides no reason to believe that under such circumstance the Netherlands research methods would not be advantageous, so this choice should be ruled out of contention.

Explanation credit: PowerScore

Hope it helps

Sajjad1994 · Answer

Explanation

7. It can be inferred from the passage that if the disease organisms mentioned in line 48 were eliminated in a plot of land that had been in constant agricultural use, which one of the following would be the most likely to occur?

Explanation

The correct answer choice is (C)

This question asks for the likely outcome if the aggressive disease organisms discussed on  line 39  were eliminated from land that had been in constant agricultural use. Such disease, researchers concluded, were the reason that seeds in overfarmed plots did not do as well as those growing in land that had been out of production for two decades. Presumably, if such disease were to be eliminated, the seeds would do better, perhaps as well as those growing naturally nearby.

Answer choice (A):  There is no basis to conclude that beneficial microorganisms would decline if the disease organisms were eliminated.

Answer choice (B):  The elimination of the disease organisms would not render unwanted species unable to survive, so this is not the right answer choice.

Answer choice (C):  This is the correct answer choice. As discussed, such seeds would likely do better if the harmful aggressive disease organisms could be eliminated; the native plant would have a better chance of survival.

Answer choice (D):  Nothing in the passage suggests that the elimination of disease organisms in over-farmed land would result in a long-term increase in the number of beneficial microorganisms.

Answer choice (E):  The author does not suggest that eliminating disease microorganisms would be likely to result in proportional increases in the population of other disease organisms, so this cannot be the right answer to this Must Be True question.

Explanation credit: PowerScore

8. Which one of the following is most analogous to the process, described in the last paragraph, by which the spread of thistles can be curtailed?

Explanation

The correct answer choice is (B)

This question asks for the process most analogous to the thistle-curtailing process described in the  last paragraph ; a mix of native grass and herb species added to plots appeared to force out the thistles.

Answer choice (A):  This choice lacks the concept of bringing in something to keep something else out, so it does not parallel the process described in the last paragraph.

Answer choice (B):  This is the correct answer choice. Like the native species supported to force out the thistles in the Netherlands study, this choice describes the approach of supporting rival candidates to take over the local area and keep Party A’s representation from proliferating.

Answer choice (C):  This choice does not parallel the process referenced in the passage, which brings in some species to force out others.

Answer choice (D):  This choice describes a more direct attack on supporters of passage A, but does not include the concept of bringing in certain species to crowd out others, so this answer fails to parallel the process described in the third paragraph and should be ruled out of contention.

Answer choice (E):  This choice deals with creation of antagonism between the parties, but it does not parallel the process outlines in the third paragraph, in which thistles appeared to have been crowded out of plots where diverse native species of grass and herbs were introduced.

Explanation credit: PowerScore

Hope it helps

auradediligodo · Answer

Hi everyone,
Took 18 minutes and got 5/8 correct. Took 4:50 minutes to read, write down paragraphs summaries and main point.

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P1 
This paragraphs talk about the plan of taking out of production thousands of acres of land to reestablish a natural balance of flora. The root cause of the problem was the over production that led to the depletion of nutrients, which in turn led to the expansion of thistles, organisms that attack plants.
There are different solutions to the problem:
#1: the most effective solution is to replace the top soil but this is unfeasible because the land is too vast
#2: leave the acres of soil alone and wait
In addition a study from the Netherlands is promising

P2 
Paragraphs 2 talks in detail about the study.
The outcome of the study is that out of all the plots analyzed the plots with the greater variety of species sown made the thistles disappear while the plots left untouched saw the thistles became dominant. 
Seems that this study can be applied to the current problem to fasten the reestablishment of the flora...

P3 
Paragraphs 3 talks about another experiment made. Soil from lands left untouched for 20 years (soil A) was put into plots of soil that was affected by overproduction(soil B). (soilA+ soil B= soil C)
The soil A used was characterized by the presence of beneficial organisms that developed over the time the soil was left untouched.
The mixed soil C fared better that the unenriched soil B but it did not fare as much as the soil A.
The reason is that in soil B there are damaging microorganisms.
The outcome of the experiment is that reestablishment of flora can be achieved by enriching soil B with beneficial microorganisms.

MP 
To discuss methods to reestablish natural flora in soils affected by overproduction

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1 . Which one of the following most accurately expresses the central idea of the passage?

Pre-thinking:
  Main point question 
Refer to main point above

(A)   The rehabilitation of land damaged by agricultural overproduction can be accelerated by means of a two-pronged strategy aimed at restoring biological diversity.
 In line with pre-thinking. Hence correct

(B) Restoring plant diversity to overused farmland requires many years and considerable effort.
 Not in line with pre-thinking. Hence incorrect

(C) The damaging effects of long-term agricultural overproduction argue for the modification of current agricultural practices.
 Not in line with pre-thinking. Hence incorrect

(D) Soil on farmland damaged by overproduction will gradually replenish and restore itself over time if left untouched.
 Not in line with pre-thinking. Hence incorrect

(E) Agricultural overproduction tends to encourage the proliferation of disease organisms in the soil as well as problem weeds.
 Not in line with pre-thinking. Hence incorrect

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2 . Which one of the following most accurately describes the organization of the passage?

Pre-thinking:
  Structure question

A problem is presented and its implications detailed--> one study and one experiment are presented as solutions to the problem

(A) A study is described, the results of the study are scrutinized, and the results are judged to be inconclusive but promising.
 Not in line with pre-thinking. Hence incorrect

(B) A hypothesis is presented, evidence both supporting and undermining the hypothesis is given, and a modification of the hypothesis is argued for.
 Not in line with pre-thinking.Plus no hypothesis. Hence incorrect

(C) A study is evaluated, a plan of action based on the study’s findings is suggested, and conclusions are drawn concerning the likely effectiveness of the plan.
 No evaluation.  Not in line with pre-thinking. Hence incorrect

(D) A goal is stated, studies are discussed that argue for modifying the goal’s objectives, and a methodology is detailed to achieve the revised goal.
 no goal but problem.  Not in line with pre-thinking. Hence incorrect

(E)   A problem is presented, a study addressing the problem is described, and a course of action based on the study’s findings is given.
 In line with pre-thinking. Hence correct

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3 . The passage offers which one of the following as an explanation for why native plant varieties grew better when sown on land that had been out of production for 20 years than when sown on the plots enriched with soil taken from that land?

Pre-thinking:

Detail question

The presence of microorganisms such as fungi were beneficial to the other soil (look above the 3rd paragraph summary for a more detailed explanation)
while the soil affected by overproduction contained damaging microorganisms

(A) Land that has been farmed for many years lacks certain key nutrients.
 Not in line with pre-thinking. Hence incorrect

(B)   Land that has been farmed for many years is usually overrun with harmful and aggressive organisms.
  in line with pre-thinking. Hence correct

(C) Land that has been farmed for many years has usually been subjected to overfertilization.
 Not in line with pre-thinking. Hence incorrect

(D) The soil that was taken from the land that had been out of production was lacking in fungi and other beneficial organisms.
 Not in line with pre-thinking. Hence incorrect

(E) The soil that was taken from the land that had been out of production contained harmful organisms that attack plant roots.
 Not in line with pre-thinking. Hence incorrect

-----------------------------------------------------------------------------------------------------

4 . Based on the passage, which one of the following is most likely to be true of any soil used to replace topsoil in the process mentioned in the first paragraph?

Pre-thinking:
  Inference question 
It should not contain harmful substances in it

(A) Thistles cannot grow in it.
 Not a strict requirement. Hence incorrect

(B) It does not contain significant amounts of fungi.
 It should actually . Hence incorrect

(C) It contains very few seeds of native grasses and herbs.
 Not necessarily. Hence incorrect

(D)   It does not contain large amounts of fertilizer.
 Fertilizers used in huge amounts contributed to the depletion of nutrients in the soil. It makes logical sense not to use it anymore. Hence correct

(E) It was never used for growing corn or other commercial crops.
 Not necessarily. Hence incorrect

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5 . The author’s reference to the belief that “damaged ecological systems will restore themselves very gradually over time” (Highlighted) primarily serves to

Pre-thinking:
  Purpose question 
Pay attention to the word  very . It suggests that the process will take a long time, maybe too much than people are willing to wait. Right after the author talks about a study that will speed up the process. So maybe the unwillingness to wait is the driver of the study aimed at speeding the process up

(A) introduce a long-held belief that the Netherlands study is attempting to discredit
 Not in line with pre-thinking. Hence incorrect

(B) cite the justification generally used by people favoring intense agricultural production
 Not in line with pre-thinking. Hence incorrect

(C) suggest that the consequences of agricultural overproduction are not as dire as people generally believe
 Not in line with pre-thinking. Hence incorrect

(D) present the most common perception of why agricultural overproduction is problematic
 Not in line with pre-thinking. Hence incorrect

(E)   describe the circumstances surrounding and motivating the Netherlands study
 In line with pre-thinking. Hence correct

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6 . In which one of the following circumstances would it be LEAST advantageous to use the methods researched in the Netherlands study in order to restore to its natural state a field that has been in constant agricultural use?

Pre-thinking:
 The study aims at finding a fast method to reestablish the flora. But what if replacing the topsoil is faster than this method?

(A) The field’s natural nutrients have been depleted through overproduction.
 Not in line with pre-thinking. Hence incorrect

(B)   The field’s topsoil can easily be removed and replaced.
 In line with pre-thinking. Hence correct

(C) The field has been heavily fertilized for many decades.
 Not in line with pre-thinking. Hence incorrect

(D) The field has the potential to support commercial grass plants such as rye.
 Not in line with pre-thinking. Hence incorrect

(E) The field is adjacent to other fields where corn is growing and will continue to be grown.
 Not in line with pre-thinking. Hence incorrect

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7 . It can be inferred from the passage that if the disease organisms mentioned in highlighted text were eliminated in a plot of land that had been in constant agricultural use, which one of the following would be the most likely to occur?

Pre-thinking:
 
 Inference question 
No damaging microorganisms= less risk for the plants

(A) Populations of symbiotic mycorrhiza that live in the soil would initially decline.
 Not in line with pre-thinking. Hence incorrect

(B) Unwanted plant species like thistles would be unable to survive.
 Not in line with pre-thinking. Hence incorrect

(C)   The chance of survival of a beneficial native plant would increase.
 In line with pre-thinking. Hence correct

(D) The number of all types of beneficial microorganisms would increase in the long term.
 Not in line with pre-thinking. Hence incorrect

(E) Populations of other types of disease organisms would increase proportionally.
 Not in line with pre-thinking. Hence incorrect

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8 . Which one of the following is most analogous to the process, described in the last paragraph, by which the spread of thistles can be curtailed?

Pre-thinking:
  analogous statement question 
The process: adding fungi-> decrease in the harmful effect of damaging microorganisms that want to attack plants

(A) A newspaper works to prevent Party A from winning a majority of seats in the legislature by publishing editorials encouraging that party’s supporters to 
switch their allegiance and vote for candidates from a rival party.
 Not analogus.

(B)   A newspaper works to prevent Party A from winning a majority of seats in the legislature by publishing editorials defending candidates from a rival party against attacks by certain broadcast journalists.
 Party A=damaging MO. Editorials=fungi. fungi defend from D MO. Correct

(C) A newspaper works to prevent Party A from winning a majority of seats in the legislature by publishing editorials intended to discourage supporters of Party A from voting in the upcoming election.
 Not analogous

(D) A newspaper works to prevent Party A from winning a majority of seats in the legislature by publishing editorials attacking certain public figures who support candidates from Party A.
 Not analogous

(E) A newspaper works to prevent Party A from winning a majority of seats in the legislature by publishing editorials intended to create antagonism between two factions within that party.
 Not analogous.

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It's a good day to be alive, cheers!

ArmaanBajaj · Answer

can someone properly explain 6?

guddo · Answer

6. In which one of the following circumstances would it be LEAST advantageous to use the methods researched in the Netherlands study in order to restore to its natural state a field that has been in constant agricultural use?

In which one of the following circumstances would it be LEAST advantageous to use the methods researched in the Netherlands study in order to restore to its natural state a field that has been in constant agricultural use?

The Netherlands study is looking for a practical alternative to removing and replacing topsoil, especially on land where that method would be difficult or 
impractical. So the method would be least useful when  topsoil replacement is already easy to do .

(A) The field’s natural nutrients have been depleted through overproduction.

Incorrect. This is exactly the kind of degraded agricultural land the study is trying to restore.

(B) The field’s topsoil can easily be removed and replaced.

Correct.   The passage explicitly says that removing and replacing topsoil is the quickest way to restore heavily fertilized land. The reason the Netherlands method is being studied is that topsoil replacement is impractical on a large scale. If it can be done easily in this field, there is much less reason to use the slower experimental approach.

(C) The field has been heavily fertilized for many decades.

Incorrect. Heavily fertilized land is especially prone to weed problems and ecological imbalance, so the researched method could be useful.

(D) The field has the potential to support commercial grass plants such as rye.

Incorrect. The field’s ability to support commercial grasses does not show that the restoration method would be disadvantageous.

(E) The field is adjacent to other fields where corn is growing and will continue to be grown.

Incorrect. This does not directly affect whether the restoration method would be useful on the field itself.

Answer: (B)

egmat · Answer

Hi ArmaanBajaj,

The tricky part of Q6 isn't the options, it's the  direction  of the question. It asks for the circumstance where the study's method is  LEAST  advantageous, so the correct answer is the one where the method brings  no benefit  - because a faster or easier option already exists. The other four will all be situations the method  helps .

So the real question becomes:  when would you not need this method at all?

Go back to paragraph 1.

The passage tells us:

"the quickest way to restore heavily fertilized land is to remove and replace the topsoil, this is impractical on a large scale."

The whole reason the Netherlands study exists is that this  quickest  fix (topsoil replacement) is usually  impractical . The study is the slower workaround for when you  can't  just swap the topsoil.

Now look at (B):

"The field's topsoil can easily be removed and replaced." If that's easy here, then the quickest method is available - so there's no reason to use the slower seeding/microorganism approach. That's exactly where the study's method gives you the  least  advantage. Correct.

Why the others are all situations where the method  does  help:

-  (A)  Depleted nutrients - the method restores soil balance. Helps.
-  (C)  Heavily fertilized for decades - this is the exact thistle problem the study targets. Helps.
-  (D)  Can support grasses like rye - sowing native grasses is part of the method. Helps.
-  (E)  Next to cornfields - nearby out-of-production land was actually a  source  of beneficial microorganisms in the study; no disadvantage created.

The key move: on a "LEAST advantageous" question, hunt for the choice that makes the method  unnecessary  - here, the one that hands you the faster alternative the passage already named.

Answer: B

As part of an international effort to address environmental problems

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As part of an international effort to address environmental problems

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