Critical Reasoning

kevincanspain wrote:
I fear we will never get an official answer for this question, as no one has ever said that it is from GMATPrep or an OG or even a test-prep company

I think there is no point discussing this question further. I googled this question on other forums, apparently this question is from VIP sets provided by "THE BANNED WEBSITE". No point discussing this further.

PS: Kevin, OA in other forums is E.

ssgmatter wrote:A certain cultivated herb is one of a group of closely related plants that thrive in soil
with high concentrations of metals that are toxic to most other plants. Agronomists
studying the herb have discovered that it produces large amounts of histidine, an
amino acid that, in test-tube solutions, renders these metals chemically inert. Possibly,
therefore, the herb's high histidine production is what allows it to grow in metal-rich
soils, a hypothesis that would gain support if ______.
A. histidine is found in all parts of the plant-roots, stem, leaves, and flowers
B. the herb's high level of histidine production is found to be associated with an
unusually low level of production of other amino acids
C. others of the closely related group of plants are also found to produce histidine
in large quantities
D. cultivation of the herb in soil with high concentrations of the metals will, over
an extended period, make the soil suitable for plants to which the metals are
toxic
E. the concentration of histidine in the growing herb declines as the plant
approaches maturity

Guys please explain this one with some good reasons.....

Its a very gud CR question. Still confused between C and D.
ssgmatter can you pls provide us the OA ??

kevincanspain wrote:Note as well that C says others, not all others.

Does the plant survive by producing a chemical that renders the metal inert? Can we extrapolate what happens in a test tube to an actual field? Was the amount of histidine added to the test tube realistic? If so, D should be true.

D, if true, provides evidence that the mechanism by which this plant survives is by rendering the metal inert. It's not that the metal has no effect on the plant: the plant actually produces a chemical that deprives the metal of its destructive properties. I think that the hypothesis would lose credibility if D were not true.

C would be MUCH more convincing if it said that plants outside this group that cannot survive do not produce histidine. If the plants are closely related, I don't find it far-fetched to suspect that many of them produce histidine.

I fear we will never get an offical answer for this question, as no one has ever said that it is from GMATPrep or an OG or even a test-prep company

So after such a long discussion, I can safely conclude that the OA is D......To some extent Kevin logic for C makes sense that it is more of the repetition of what is there in the argument....

Let me know if anybody has a different thought on this..

Under experimental conditions the chemical by the plants leaves the metal inert. Now this could be the reason why the plants are able to grow in metal rich soil if it is shown that the soil has been neutralized (something similar to the test tube condition). Hence D.

I still think OA should be E . Experts please suggest

ssgmatter wrote:A certain cultivated herb is one of a group of closely related plants that thrive in soil
with high concentrations of metals that are toxic to most other plants. Agronomists
studying the herb have discovered that it produces large amounts of histidine, an
amino acid that, in test-tube solutions, renders these metals chemically inert. Possibly,
therefore, the herb's high histidine production is what allows it to grow in metal-rich
soils, a hypothesis that would gain support if ______.
A. histidine is found in all parts of the plant-roots, stem, leaves, and flowers
B. the herb's high level of histidine production is found to be associated with an
unusually low level of production of other amino acids
C. others of the closely related group of plants are also found to produce histidine
in large quantities
D. cultivation of the herb in soil with high concentrations of the metals will, over
an extended period, make the soil suitable for plants to which the metals are
toxic.
E. the concentration of histidine in the growing herb declines as the plant
approaches maturity

Guys please explain this one with some good reasons.....

I received a PM asking me to comment.

This is a CAUSAL argument.
In a causal argument, A and B are observed together, and the CR concludes that A CAUSES B.

Premise = A and B are observed together:
A cultivated herb produces histidine and is able to grow in metal rich soils.
Conclusion = A causes B:
Histidine CAUSES the herb to be able to grow in metal rich soils.

One way to strengthen the conclusion that A causes B is give ANOTHER SUPPORTING EXAMPLE that links A to B.
C: others of the closely related group of plants are also found to produce histidine in large quantities.
Here, other plants in the closely related group THAT THRIVE IN SOIL WITH HIGH CONCENTRATIONS OF METALS also produce HISTIDINE, STRENGTHENING the conclusion that histidine CAUSES a plant to be able to grow in metal-rich soils.

The correct answer is C.

E IS CORRECT.

this question is from 15 test sets which is a part of GMATPREP quesions. VERY GOOD SOURCE, THE ONLY OFFICIAL SOURCE OF HARD QUESTIONS.

This is causal relation.

Argument said histidine causes inertness of toxic

In E, maturity means no growth, and E means no histidine-no growth

no cause-no effect strengthen the causal relation.

why D is wrong. The argument is about relation between inertness of toxic and the histidy IN THE PLANT, NOT IN THE SOIL. D is attractive because it is wrong a little.

what make it difficult to realize E?

we have to infer from maturity into NO GROWTH. This trick gmat do on many questions on GMATPREP.

FOR HARDER QUESTIONS, WE NEED TO INFER NECCESSARY INFORMATION FROM THE INFORMATION IN THE ANSWER CHOICE BEFORE CONSIDER THE AFFECT OF THIS ANSWER CHOICE ON THE LINK, ON THE CONCLUSION. (FOR ALL ASSUMPTION BASED QUESTIONS)

I do this question in more than 3 minutes. This means I die already.

this is 800 level question. NEVER UNDERESTIMATE THE GMATPREP QUESTIONS.

A SIMILAR QUESTION IN GMATPREP IS the one " the birds which eat pesticide". In this question, the test maker make the INFERENCE TRICK exactly the way he/she make inhere.

IF ANYONE WANT MORE QUESTIONS OF THIS TRICK, EMAIL ME.

good luck.

Can you please provide us the proof that OA is E so that our experts can further comment on it .

duongthang wrote:E IS CORRECT.

this question is from 15 test sets which is a part of GMATPREP quesions. VERY GOOD SOURCE, THE ONLY OFFICIAL SOURCE OF HARD QUESTIONS.

This is causal relation.

Argument said histidine causes inertness of toxic

In E, maturity means no growth, and E means no histidine-no growth

no cause-no effect strengthen the causal relation.

why D is wrong. The argument is about relation between inertness of toxic and the histidy IN THE PLANT, NOT IN THE SOIL. D is attractive because it is wrong a little.

what make it difficult to realize E?

we have to infer from maturity into NO GROWTH. This trick gmat do on many questions on GMATPREP.

FOR HARDER QUESTIONS, WE NEED TO INFER NECCESSARY INFORMATION FROM THE INFORMATION IN THE ANSWER CHOICE BEFORE CONSIDER THE AFFECT OF THIS ANSWER CHOICE ON THE LINK, ON THE CONCLUSION. (FOR ALL ASSUMPTION BASED QUESTIONS)

I do this question in more than 3 minutes. This means I die already.

this is 800 level question. NEVER UNDERESTIMATE THE GMATPREP QUESTIONS.

A SIMILAR QUESTION IN GMATPREP IS the one " the birds which eat pesticide". In this question, the test maker make the INFERENCE TRICK exactly the way he/she make inhere.

IF ANYONE WANT MORE QUESTIONS OF THIS TRICK, EMAIL ME.

good luck.

To meet the author's prediction based on Agronomists's study, the hypothesis has to show casual relation between the histidine and the growth of herb in soil with metals that are toxic to other plants.

Answer choices A, B, and C are irrelevant because they do not have necessary casual relation. But, answer choice D brings in a casual relation that cultivation of the herb over an extended period drives the growth of herb. cultivation of the herb over an extended period is not distinct and can naturally be applied to other plants too. However, answer choice E brings in a close casual relation that the concentration of histidine declines as the pant matures (indirectly says the histidine helped the plant to grow). I think the E is not ideal answer but best in the given options.

GMATGuruNY wrote:

ssgmatter wrote:A certain cultivated herb is one of a group of closely related plants that thrive in soil
with high concentrations of metals that are toxic to most other plants. Agronomists
studying the herb have discovered that it produces large amounts of histidine, an
amino acid that, in test-tube solutions, renders these metals chemically inert. Possibly,
therefore, the herb's high histidine production is what allows it to grow in metal-rich
soils, a hypothesis that would gain support if ______.
A. histidine is found in all parts of the plant-roots, stem, leaves, and flowers
B. the herb's high level of histidine production is found to be associated with an
unusually low level of production of other amino acids
C. others of the closely related group of plants are also found to produce histidine
in large quantities
D. cultivation of the herb in soil with high concentrations of the metals will, over
an extended period, make the soil suitable for plants to which the metals are
toxic.
E. the concentration of histidine in the growing herb declines as the plant
approaches maturity

Guys please explain this one with some good reasons.....

I received a PM asking me to comment.

I'm with Kevin.

The premise is about how histidine renders the metals chemically inert.
The conclusion is that this process allows the herb to grow in the soil.

The correct answer must connect these two ideas: it must show that if the metals are rendered chemically inert, then a plant can grow in the soil.

Answer choice D makes the necessary connection: Cultivation of the herb in soil with high concentrations of the metals will, over an extended period -- during which time the histidine will render the metals chemically inert, according to the passage -- make the soil suitable for plants to which the metals are toxic. This answer choice connects how the herb renders the metals chemically inert with the ability of plants to grow in the soil.

The correct answer is D.

Answer choice C discusses only others of the closely related group. How many others? Others could mean only two out of thousands. If histidine is the reason that the plants can thrive, then MOST of the members (if not every every member) of the closely related group should produce histidine.

More importantly, answer choice C suggests the following: frequency = causality. Not necessarily. Imagine the following:

John Wilson belongs to a family whose members consistently get high grades. John wears a red shirt every day. Possibly, therefore, wearing a red shirt is what allows John to get high grades, a hypothesis that would gain support if ______.

C: other members of the Wilson family wear red shirts every day.

Does answer choice C seem correct here?

I google search this question which is discussed on many forum. yes, OA is E.

E supports that hadistine causes growth.
D,C support that hadistine cause inertness

we do not realize the conclusion/hypothesis and choose D or C.

MANY GMATPREP QUESTIONS, HARD QUESTIONS, MAKE US MISTAKE CONCLUSION AND QUESTION. these are trick, though simple but fatal to us. GMATPREP even do not use hard logic to fail us. It use simple trick like this. GMATPREP test simple thing, reading carefully.