Guys, I am stuck on the CR mentioned below -
The chanterelle, a type of wild mushroom, grows beneath host trees such as the Douglas fir, which provide it with necessary sugars. The underground filaments of chanterelles, which extract the sugars, in turn provide nutrients and water for their hosts. Because of this mutually beneficial relationship, harvesting the chanterelles growing beneath a Douglas fir seriously endangers the tree. Which of the following, if true, casts the most doubt on the conclusion drawn above?
(A) The number of wild mushrooms harvested has increased in recent years.
(B) Chanterelles grow not only beneath Douglas firs but also beneath other host trees.
(C) Many types of wild mushrooms are found only in forests and cannot easily be grown elsewhere.
(D) The harvesting of wild mushrooms stimulates future growth of those mushrooms.
(E) Young Douglas fir seedlings die without the nutrients and water provided by chanterelle filaments.
OA after some discussion
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Chanterelle & Douglas Fir
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Bill@VeritasPrep
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The conclusion is that harvesting the mushrooms will endanger the tree. Why? The mushrooms provide nutrients and water for the tree.
We're looking for answer that would weaken the conclusion.
A is irrelevant to whether harvesting those mushrooms endangers their host trees.
B is also irrelevant; we don't have information on other trees.
C has nothing to do with the potential harm caused by harvesting the mushrooms.
D is good. If harvesting actually stimulates the growth of more mushrooms, it could actually be beneficial to the tree.
E is a good strengthen answer.
We're looking for answer that would weaken the conclusion.
A is irrelevant to whether harvesting those mushrooms endangers their host trees.
B is also irrelevant; we don't have information on other trees.
C has nothing to do with the potential harm caused by harvesting the mushrooms.
D is good. If harvesting actually stimulates the growth of more mushrooms, it could actually be beneficial to the tree.
E is a good strengthen answer.
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camitava
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Thanks Bill for your quick reply. I agree with your explanation. I will also go with option E because it shows the mutual benefits between between wild mushroom and Douglas FIR. If the mushroom is removed, Fir would subsequently lose its life. But to my utter astonishment, the OA for this is D. I fail to understand how D could be an OA for such a CR? If my explanation is wrong, let me know where my fault is.Bill@VeritasPrep wrote:The conclusion is that harvesting the mushrooms will endanger the tree. Why? The mushrooms provide nutrients and water for the tree.
We're looking for answer that would weaken the conclusion.
A is irrelevant to whether harvesting those mushrooms endangers their host trees.
B is also irrelevant; we don't have information on other trees.
C has nothing to do with the potential harm caused by harvesting the mushrooms.
D is good. If harvesting actually stimulates the growth of more mushrooms, it could actually be beneficial to the tree.
E is a good strengthen answer.
Correct me If I am wrong
Regards,
Amitava
Regards,
Amitava
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Bill@VeritasPrep
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This is a Weaken question, and E is a Strengthen answer.
The conclusion is at the end of the stimulus: "harvesting the chanterelles growing beneath a Douglas fir seriously endangers the tree." The stem asks us to cast doubt on it, or to give a reason that harvesting may not be as harmful to the tree as it seems.
E shows how it absolutely is harmful. It supports the idea that harvesting = danger.
D casts doubt on the harvesting = danger idea by showing that the tree may actually see benefits if harvesting leads to more mushrooms that can provide it with nutrients and water.
The conclusion is at the end of the stimulus: "harvesting the chanterelles growing beneath a Douglas fir seriously endangers the tree." The stem asks us to cast doubt on it, or to give a reason that harvesting may not be as harmful to the tree as it seems.
E shows how it absolutely is harmful. It supports the idea that harvesting = danger.
D casts doubt on the harvesting = danger idea by showing that the tree may actually see benefits if harvesting leads to more mushrooms that can provide it with nutrients and water.
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Abhishek009
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chanterelle - Wild Mushroom grows beneath host trees and extracts necessary sugars.camitava wrote:The chanterelle, a type of wild mushroom, grows beneath host trees such as the Douglas fir, which provide it with necessary sugars. The underground filaments of chanterelles, which extract the sugars, in turn provide nutrients and water for their hosts. Because of this mutually beneficial relationship, harvesting the chanterelles growing beneath a Douglas fir seriously endangers the tree.
chanterelle - In return provides the host plant with nutrients and water.
Hence Harvesting chanterelle beneath host plants seriously endangers the tree.
Which of the following, if true, casts the most doubt on the conclusion drawn above?
Check the passage carefully , the passage mentions that the parasitic plant ectracts sugar from its hosts but in return provides the plant with necessary water and sugar. There is nothing to prove the harmful effects of the parasite.
(A) The number of wild mushrooms harvested has increased in recent years.
Irrelevant , number has no role here.
(B) Chanterelles grow not only beneath Douglas firs but also beneath other host trees.
Might be true , but how is it related here...
(C) Many types of wild mushrooms are found only in forests and cannot easily be grown elsewhere.
So what , we are talking about wilkd mushrooms , they are expected to grow in wild areas.
(D) The harvesting of wild mushrooms stimulates future growth of those mushrooms.
OK , might be true , how is it related to the conclusion drawn here.
(E) Young Douglas fir seedlings die without the nutrients and water provided by chanterelle filaments.
If the host plant dies without the support of the Parasitic plant then it is expected to grom more of such parasitic plant beneath the Host Plant.
Hence IMO (E) suits the best..
Abhishek
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Hi Abhishek009 and camitava,
This CR question is a 'Weaken' question; to correctly answer it, you need to understand the logic behind the question and then find an answer that ATTACKS the logic.
The Facts:
-The chanterelle (a mushroom) grows beneath host trees (such as the Douglas Fir).
-The host tree provides the mush with necessary sugars
-The mushroom provides nutrients and water to the hosts (the trees).
-The relationship between the mushrooms and the trees is mutually beneficial.
The Conclusion:
-Harvesting chanterelles growing beneath a Douglas fir SERIOUSLY ENDANGERS THE TREE.
The Logic:
-The chanterelles are really important to keeping the host tree alive. Harvesting chanterelles removes the benefit that they provide.
To WEAKEN the logic, we need an answer that tells us something to the effect that chanterelles are NOT that important to keeping the Douglas Fir tree alive OR that removing the chanterelles DOES NOT remove the benefit to the Douglas Fir tree.
Since the discussion seems to be between answers D and E, I'll offer some insight into those 2 answers.
Answer D tells us that removing the chanterelles stimulates future grown of the mushrooms, so the benefit is NOT removed.
Answer E tells us that the trees will die without the chanterelles; this is the OPPOSITE of what we're looking for (since the question asked us to Weaken the logic and this answer Strengthens the logic).
Final Answer: D
GMAT assassins aren't born, they're made,
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This CR question is a 'Weaken' question; to correctly answer it, you need to understand the logic behind the question and then find an answer that ATTACKS the logic.
The Facts:
-The chanterelle (a mushroom) grows beneath host trees (such as the Douglas Fir).
-The host tree provides the mush with necessary sugars
-The mushroom provides nutrients and water to the hosts (the trees).
-The relationship between the mushrooms and the trees is mutually beneficial.
The Conclusion:
-Harvesting chanterelles growing beneath a Douglas fir SERIOUSLY ENDANGERS THE TREE.
The Logic:
-The chanterelles are really important to keeping the host tree alive. Harvesting chanterelles removes the benefit that they provide.
To WEAKEN the logic, we need an answer that tells us something to the effect that chanterelles are NOT that important to keeping the Douglas Fir tree alive OR that removing the chanterelles DOES NOT remove the benefit to the Douglas Fir tree.
Since the discussion seems to be between answers D and E, I'll offer some insight into those 2 answers.
Answer D tells us that removing the chanterelles stimulates future grown of the mushrooms, so the benefit is NOT removed.
Answer E tells us that the trees will die without the chanterelles; this is the OPPOSITE of what we're looking for (since the question asked us to Weaken the logic and this answer Strengthens the logic).
Final Answer: D
GMAT assassins aren't born, they're made,
Rich
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camitava
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Thanks for keeping the discussion alive. I read the argument several times and list of answer choices given here. I understood that probably two points are making us confusing. The first one is -
Now about the second point -
The argument is also saying the same thing and it is matching with the conclusion. Or in other word, it is agreeing with the conclusion that growing mushroom, chanterelles would endanger the life of DOuglas Fir. How are you choosing D then? I got confused here.
From mutually beneficial relationship, we expect both the parties will be benefited but not endanger about one's existance. For the sake of argument, we do not have our opinion open but understand what this argument is talking about. We admitted that growing the wild mushroom, chanterelle, would endanger the fir, Douglas fir.Because of this mutually beneficial relationship, harvesting the chanterelles growing beneath a Douglas fir seriously endangers the tree.
Now about the second point -
This option is mentioning the word "mushroom" twice and I understood that it meant the same wild mushroom chanterelles in both the times. Here we haveone mushroom chanterelles and one fir Douglas Fir. If we harvest chanterelles, it would stimulate growth of the chanterelles. Now if we go with the argument, we can easily conclude that growing mushroom, chanterelles will endanger the life of Douglas Fir.The harvesting of wild mushrooms stimulates future growth of those mushrooms
The argument is also saying the same thing and it is matching with the conclusion. Or in other word, it is agreeing with the conclusion that growing mushroom, chanterelles would endanger the life of DOuglas Fir. How are you choosing D then? I got confused here.
Correct me If I am wrong
Regards,
Amitava
Regards,
Amitava
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camitava
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Thanks for keeping the discussion alive. I read the argument several times and list of answer choices given here. I understood that probably two points are making us confusing. The first one is -
Now about the second point -
The argument is also saying the same thing and it is matching with the conclusion. Or in other word, it is agreeing with the conclusion that growing mushroom, chanterelles would endanger the life of DOuglas Fir. How are you choosing D then? I got confused here.
From mutually beneficial relationship, we expect both the parties will be benefited but not endanger about one's existance. For the sake of argument, we do not have our opinion open but understand what this argument is talking about. We admitted that growing the wild mushroom, chanterelle, would endanger the fir, Douglas fir.Because of this mutually beneficial relationship, harvesting the chanterelles growing beneath a Douglas fir seriously endangers the tree.
Now about the second point -
This option is mentioning the word "mushroom" twice and I understood that it meant the same wild mushroom chanterelles in both the times. Here we haveone mushroom chanterelles and one fir Douglas Fir. If we harvest chanterelles, it would stimulate growth of the chanterelles. Now if we go with the argument, we can easily conclude that growing mushroom, chanterelles will endanger the life of Douglas Fir.The harvesting of wild mushrooms stimulates future growth of those mushrooms
The argument is also saying the same thing and it is matching with the conclusion. Or in other word, it is agreeing with the conclusion that growing mushroom, chanterelles would endanger the life of DOuglas Fir. How are you choosing D then? I got confused here.
Correct me If I am wrong
Regards,
Amitava
Regards,
Amitava
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Bill@VeritasPrep
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It's not the growing of the mushrooms that supposedly endangers the tree, it's the harvesting (or removal) of the mushrooms that supposedly endangers the tree. I think this may be the part that you're having trouble with.camitava wrote:
From mutually beneficial relationship, we expect both the parties will be benefited but not endanger about one's existance. For the sake of argument, we do not have our opinion open but understand what this argument is talking about. We admitted that growing the wild mushroom, chanterelle, would endanger the fir, Douglas fir.
If you read the argument as "removing the mushrooms may harm the tree", then choice E essentially says "firs die when the mushrooms are removed" which fits perfectly with the conclusion. It's a good strengthen answer.
D says "removing the mushrooms leads to more mushrooms growing" and since the mushrooms provide nutrients and water, the tree might actually benefit, thus contradicting the idea that the trees will suffer.
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