Knewton Challenge, 1/24/11 (Glucose Intolerance)

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Hey everyone,

Here's the Knewton Verbal Challenge question for Monday, 1/24. Once you've looked it over, reply to this thread with your answer and an explanation for how you got it. Just like last week, I'll choose the best explanation at 11 pm EST, and the daily winner will get free access to the Beat the GMAT Practice Questions!

Again, congrats to Friday's winner, aspirant_gmat!

--

Question 4.

Diabetes is a disease in which the body does not produce or properly use insulin, a hormone that is needed to convert glucose into energy needed for daily life. Because ice cream commonly contains glucose in the form of sucrose, diabetics generally experience discomfort after consuming even a small serving of ice cream. However, since there are several ice cream companies who add sucrose to none of the ice cream they produce, diabetics are able to eat ice cream without experiencing discomfort due to glucose intolerance afterward.

Which of the following is an assumption on which the argument depends?

(A) These ice cream companies have been able to duplicate the taste of sucrose derived from glucose by means that do not involve adding any potential substances that may be of discomfort to diabetics.
(B) Not all forms of glucose are equally likely to result in this discomfort.
(C) Ice cream is not the only food to which glucose is commonly added.
(D) Apart from glucose, there are no substances commonly present in ice cream that would cause discomfort to diabetics.
(E) Glucose is not naturally present in the ice cream produced by these ice cream companies in amounts large enough to cause discomfort to diabetics who eat this ice cream.
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by gnod » Mon Jan 24, 2011 6:02 am
[PREMISE] Diabetes is a disease in which the body does not produce or properly use insulin, a hormone that is needed to convert glucose into energy needed for daily life.

[CLAIM] Because ice cream commonly contains glucose in the form of sucrose, diabetics generally experience discomfort after consuming even a small serving of ice cream.

[CONCLUSION]However, since there are several ice cream companies who add sucrose to none of the ice cream they produce, diabetics are able to eat ice cream without experiencing discomfort due to glucose intolerance afterward.

Which of the following is an assumption on which the argument depends?

(A) These ice cream companies have been able to duplicate the taste of sucrose derived from glucose by means that do not involve adding any potential substances that may be of discomfort to diabetics.
(B) Not all forms of glucose are equally likely to result in this discomfort.
(C) Ice cream is not the only food to which glucose is commonly added.
(D) Apart from glucose, there are no substances commonly present in ice cream that would cause discomfort to diabetics.
(E) Glucose is not naturally present in the ice cream produced by these ice cream companies in amounts large enough to cause discomfort to diabetics who eat this ice cream.

Answer (D)

The claim is that diabetics experience discomfort after eating ice cream containing glucose in the form of sucrose.

The conclusion is that diabetics can eat ice cream from companies who add sucrose to none of the ice cream they produce.

BUT - the author fails to connect whether or not if there are other forms of glucose in the form of another ingredient.

Therefore - the author must assume that the only glucose in ice cream is in the form of sucrose and nothing else.

Wrong Answers:

A) To me - this was the trap-choice. The fact that ice cream companies might add some other ingredient to ensure the taste of the ice cream stays the same is plausible - but in no where in the prompt is the 'taste' of the ice cream an issue. Therefore, it's outside of the scope.
B) Whether or not all forms of glucose equally result in discomfort doesn't really build the argument. The argument is that diabetics can enjoy ice cream without glucose in the form of sucrose.
C) This is outside of scope - the prompt is specifically talking about ice cream.
D) Correct answer
E) The fact that glucose is not naturally present in ice cream doesn't help the argument. The argument again is that, diabetics can eat ice cream without sucrose - we don't know what ice cream companies do from the natural state of the ice cream, to the possibly altered, glucose free ice cream.

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by AIM GMAT » Mon Jan 24, 2011 6:18 am
IMO E.

A] This option is incorrect because the argument scope is not concerned with discomfort by any other potential substance . Out of scope.

B] All forms of glucose is out of scope of argument to be discussed. We are talking about glucose in form of sucrose.

C] Again , this is talking about that ice cream is not only source , we are not allowed to discuss other sources over here in this argument.

D] The argument is concerned with discomfort arising due to consumption of glucose and not the other substances . Irrelevant.

E] This is the assumption made by the argument , as this fills the gap . The argument is valid only if glucose is not naturally occuring in ice cream produced. Without this the argument will fall apart.So if glucose is naturally present in ice cream produced , even if some companies do not add sucrose the ice cream will be harmful for diabetics and will cause discomfort.
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by jaymw » Mon Jan 24, 2011 6:45 am
thanks AIM GMAT and GMATMadeeasy. I see that overreading "glucose intolerance" can have severe consequences :(
Last edited by jaymw on Mon Jan 24, 2011 7:33 am, edited 2 times in total.

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by geekforu » Mon Jan 24, 2011 6:48 am
AdamKnewton wrote:Hey everyone,

Here's the Knewton Verbal Challenge question for Monday, 1/24. Once you've looked it over, reply to this thread with your answer and an explanation for how you got it. Just like last week, I'll choose the best explanation at 11 pm EST, and the daily winner will get free access to the Beat the GMAT Practice Questions!

Again, congrats to Friday's winner, aspirant_gmat!

--

Question 4.

Diabetes is a disease in which the body does not produce or properly use insulin, a hormone that is needed to convert glucose into energy needed for daily life. Because ice cream commonly contains glucose in the form of sucrose, diabetics generally experience discomfort after consuming even a small serving of ice cream. However, since there are several ice cream companies who add sucrose to none of the ice cream they produce, diabetics are able to eat ice cream without experiencing discomfort due to glucose intolerance afterward.

Which of the following is an assumption on which the argument depends?

(A) These ice cream companies have been able to duplicate the taste of sucrose derived from glucose by means that do not involve adding any potential substances that may be of discomfort to diabetics.
(B) Not all forms of glucose are equally likely to result in this discomfort.
(C) Ice cream is not the only food to which glucose is commonly added.
(D) Apart from glucose, there are no substances commonly present in ice cream that would cause discomfort to diabetics.
(E) Glucose is not naturally present in the ice cream produced by these ice cream companies in amounts large enough to cause discomfort to diabetics who eat this ice cream.

(A) Nothing is mentioned regarding addition of substances to duplicate the taste of sucrose - out of scope

(B) We are discussing about glucose in ice creams and not about other forms of glucose - out of scope

(C)Similar to above, we are discussing only about ice creams and not other food - irrelevant

(D) This logically completes the passage. The author says that

"Because ice cream commonly contains glucose in the form of sucrose, diabetics generally experience discomfort after consuming even a small serving of ice cream"

This would be logically incomplete unless we assume that no other substance present in the ice cream had caused the discomfort and it is only glucose which actually did. Correct ans.

(E) Nothing is mentioned about natural occurence of glucose in the ice cream manufactured by these companies - irrelevant


IMO Ans : (D)

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by GMATMadeEasy » Mon Jan 24, 2011 7:14 am
Answer should be E .
Assumption question here asks for to look for whole in the argument , and answer has to be minimal needed to protect the argument. (we can also do a negation test)
Premise1: Diabetes is a disease in which the body does not produce or properly use insulin, a hormone that is needed to convert glucose into energy needed for daily life.
Premise 2: Because ice cream commonly contains glucose in the form of sucrose, diabetics generally experience discomfort after consuming even a small serving of ice cream .
Premise3: However, There are several ice cream companies who add sucrose to none of the ice cream they produce .
Conclusion : Diabetics are able to eat ice cream without experiencing discomfort due to glucose intolerance afterward.

the author of the argument mentions the importance of insulin and goes on saying that its absence causes discomfort.
No glucose to energy conversion - > discomfort
icecream manufacturer does not add glucose - > no discomfort . The argument falsely assumes here that there is presence of glucose in ice-cream only if it is added externally. What if there is glucose already in ice-cream, then it will lead to discomfort as well .

A> Incorrect: We are not interested in taste of ice-cream but the discomfort caused by presence of glucose in diabetic people. (Out of scope)
B> Incorrect: We do not need to assume this extreme for the argument to be true. Negation: If some forms of glucose leads to disocmfort,conclusion holds true. (Extreme )
C Incorrect : Argument talks about only icec ream , it does not need to assume that glucose is present in other eatables as well.
D Incorrect: First I thought of this but minimal thing and a close look suggests me that it can't be the answer. Conclusion mentions clearly "diabetics are able to eat ice cream without experiencing discomfort due to glucose intolerance afterward. so we are interested caused by glucose."
E Correct: As explained earlier, negation of the statement is: "Glucose is naturally present in the ice cream produced by these ice cream companies in amounts large enough to cause discomfort to diabetics who eat this ice cream."

This destroys the argument .

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by gmat1011 » Mon Jan 24, 2011 7:20 am
IMO answer is E.

Conclusion: diabetics are able to eat [certain types of] ice cream without experiencing discomfort due to glucose intolerance afterward BECAUSE [there are several ice cream companies who add sucrose to none of the ice cream they produce]

We are looking for an assumption that supports why certain types of ice cream can be consumed by diabetics without experiencing discomfort DUE TO glucose intolerance. WE ARE ONLY INTERESTED IN THE TYPE OF DISCOMFORT THAT IS CAUSED BY GLUCOSE INTOLERANCE and not other types of discomfort.

Option E: Glucose is not naturally present in the ice cream produced by these ice cream companies in amounts large enough to cause discomfort to diabetics who eat this ice cream.

By negating this option we can confirm that this is a relevant assumption. Result of negation: Glucose in naturally present in ice cream... in amounts large enough to cause discomfort to diabetics. If this the case then the conclusion about diabetics being able to consume sucrose-free ice cream without discomfort falls apart as the naturally occurring glucose will result in discomfort.

Other options

A --- No - the taste of sucrose and the method by which it is achieved is not relevant to the conclusion that pertains to discomfort caused due to glucose intolerance

B --- No - the likelihood of causing discomfort is not in issue. This assumption is not relevant to the conclusion that pertains to discomfort caused due to glucose intolerance

C --- No - one need not assume that there are other foods to which glucose is commonly added. Addition of glucose to other foods has no relevance to the argument about discomfort caused due to glucose intolerance

D --- No - "discomfort to diabetics" is too broad in this option. he only type of discomfort the argument is concerned with is discomfort "caused due to glucose intolerance." One need not assume "there are no other substances (other than glucose)" present in the ice cream as these other substances are not related to discomfort due to glucose intolerance.

An assumption is "necessary" and must be true for the argument to stand. Option D fails this test and purports to assume something that is not necessary or relevant.

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by towerSpider » Mon Jan 24, 2011 7:22 am
A: A is wrong because we nothing know if companies try to duplicate the taste. It looks out of scope.

B: Either way it does not watter. Falsifying or waking true this fact does not alter the argument.

C: Either way it does not matter. WRONG.

D. WRONG. It is already stated. It is premise.

E: This is correct. Companies do not add their own and thus have ice cream which IS NOT PROBLEMATIC. It means there is no natural glucose present in ice cream (or upto certain problematic level). Because if it was not true (assumed), we still would have problem causing ice cream.
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by stormier » Mon Jan 24, 2011 9:18 am
AdamKnewton wrote:Hey everyone,

Here's the Knewton Verbal Challenge question for Monday, 1/24. Once you've looked it over, reply to this thread with your answer and an explanation for how you got it. Just like last week, I'll choose the best explanation at 11 pm EST, and the daily winner will get free access to the Beat the GMAT Practice Questions!

Again, congrats to Friday's winner, aspirant_gmat!

--

Question 4.

Diabetes is a disease in which the body does not produce or properly use insulin, a hormone that is needed to convert glucose into energy needed for daily life. Because ice cream commonly contains glucose in the form of sucrose, diabetics generally experience discomfort after consuming even a small serving of ice cream. However, since there are several ice cream companies who add sucrose to none of the ice cream they produce, diabetics are able to eat ice cream without experiencing discomfort due to glucose intolerance afterward.


Conclusion - absence of glucose in the ice cream allows diabetics to eat the ice cream without discomfort.

The argument is about discomfort caused by glucose intolerance, and not about discomfort to diabetics caused by other substances.



Which of the following is an assumption on which the argument depends?



(A) These ice cream companies have been able to duplicate the taste of sucrose derived from glucose by means that do not involve adding any potential substances that may be of discomfort to diabetics.

Incorrect. Taste of the ice cream is not relevant to the point of contention. Let's negate the answer choice and say that the ice cream companies have not been able to duplicate the taste by making it diabetic friendly. The argument still holds - because diabetics could still eat the tasteless ice cream and not experience discomfort.

(B) Not all forms of glucose are equally likely to result in this discomfort.

Incorrect. Likelihood of discomfort is not the point at stake. Any form of glucose will cause discomfort according to the premise stated in the stimulus. Thus this answer choice is irrelevant.

(C) Ice cream is not the only food to which glucose is commonly added.

Incorrect. Irrelevant - Whether glucose is added to foods other than ice cream has no bearing on the discomfort that ice cream may cause to the diabetics.

(D) Apart from glucose, there are no substances commonly present in ice cream that would cause discomfort to diabetics.

Incorrect. This is a very tricky answer choice. The argument is about discomfort caused due to glucose intolerance and not about discomfort due to other substances that may be present in the ice cream. This answer choice, although very attractive, is at best irrelevant.

(E) Glucose is not naturally present in the ice cream produced by these ice cream companies in amounts large enough to cause discomfort to diabetics who eat this ice cream.

Correct. Let's negate this choice. Glucose is naturally present in the ice cream produced by these companies in amounts large enough to cause discomfort to diabetics. The argument falls apart. It directly attacks the conclusion - saying that the glucose that is naturally present will cause discomfort to diabetics due to glucose intolerance.

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by hja379 » Mon Jan 24, 2011 9:20 am
IMO: E

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by RACHVIK » Mon Jan 24, 2011 9:50 am
The correct is indeed E.

the argument states that glucose consumption causes discomfort to diabetics. When diabetics eat ice cream containing Glucose (present in form of sucrose), they feel discomfort. Then author goes on to conclude that when diabetics eat ice cream not containing sucrose, they do not feel discomfort.

This leads one to believe that sucrose is the only form in which glucose can be present in ice cream. The argument states that glucose is present as sucrose but does not state that glucose is present only as sucrose. If removing sucrose (source for glucose) removes discomfort, it implies glucose is not present in any other form.

Option E nails it by stating that glucose in not present naturally in ice cream in substantial form to cause discomfort. If we negate this premise, it states that Glucose is naturally present in ice cream in substantial form to cause discomfort, which makes the conclusion fall apart: no sucrose - no discomfort.

(A) These ice cream companies have been able to duplicate the taste of sucrose derived from glucose by means that do not involve adding any potential substances that may be of discomfort to diabetics.

This argument does not address the main point: removing sucrose removes discomfort. substituting taste of sucrose is irrelevant.

(B) Not all forms of glucose are equally likely to result in this discomfort.

the argument deals with sucrose , so other forms are out of scope.

(C) Ice cream is not the only food to which glucose is commonly added.

the argument deals with ice creams only. so out of scope.

(D) Apart from glucose, there are no substances commonly present in ice cream that would cause discomfort to diabetics.

the argument addresses discomfort linked to glucose, so this is out of scope.

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by mbadoc13 » Mon Jan 24, 2011 10:07 am
Premise 1 : Diabetes is a disease in which the body does not produce or properly use insulin, a hormone that is needed to convert glucose into energy needed for daily life.
Premise 2 : Because ice cream commonly contains glucose in the form of sucrose, diabetics generally experience discomfort after consuming even a small serving of ice cream.
Premise 3 : However, since there are several ice cream companies who add sucrose to none of the ice cream they produce,
Conclusion : diabetics are able to eat ice cream without experiencing discomfort due to glucose intolerance afterward.

Which of the following is an assumption on which the argument depends?

(A) These ice cream companies have been able to duplicate the taste of sucrose derived from glucose by means that do not involve adding any potential substances that may be of discomfort to diabetics.. Gives us additional information that the conclusion had not assumed. Also taste is out of scope.
(B) Not all forms of glucose are equally likely to result in this discomfort. Out of scope . Argument is talking only about ice cream and sucrose. whether the companies had added other forms of glucose to replace sucrose is not discussed here
(C) Ice cream is not the only food to which glucose is commonly added. Out of scope . Argument is talking only about ice cream and sucrose
(D) Apart from glucose, there are no substances commonly present in ice cream that would cause discomfort to diabetics.
Out of scope. Conclusion talks about discomfort due to glucose intolerance only
(E) Glucose is not naturally present in the ice cream produced by these ice cream companies in amounts large enough to cause discomfort to diabetics who eat this ice cream. Correct This is a tricky choice. It plays on the word "add". Premise 2 clearly states that glucose is present in the form of sucrose and premise 3 says that the companies do not add sucrose so this statement is likely to be true and is assumed. [/b]

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by aspirant_gmat » Mon Jan 24, 2011 10:08 am
Diabetes is a disease in which the body does not produce or properly use insulin, a hormone that is needed to convert glucose into energy needed for daily life. Because ice cream commonly contains glucose in the form of sucrose, diabetics generally experience discomfort after consuming even a small serving of ice cream. However, since there are several ice cream companies who add sucrose to none of the ice cream they produce, diabetics are able to eat ice cream without experiencing discomfort due to glucose intolerance afterward.

Which of the following is an assumption on which the argument depends?

(A) These ice cream companies have been able to duplicate the taste of sucrose derived from glucose by means that do not involve adding any potential substances that may be of discomfort to diabetics.
(B) Not all forms of glucose are equally likely to result in this discomfort.
(C) Ice cream is not the only food to which glucose is commonly added.
(D) Apart from glucose, there are no substances commonly present in ice cream that would cause discomfort to diabetics.
(E) Glucose is not naturally present in the ice cream produced by these ice cream companies in amounts large enough to cause discomfort to diabetics who eat this ice cream.

The conclusion is based on the fact that

When a diabetic person eats an ice cream, he/she feels discomfort due to glucose intolerance, because
ice creams normally contain glucose in the form of sucrose.

We can rewrite the above mentioned fact as follows:

X< discomfort due to glucose intolerance> is caused by Y< sucrose added to the ice cream>

And the conclusion is:

If a diabetic person eats an ice cream that doesn't have sucrose added to it, the person won't feel discomfort due to glucose intolerance.

The conclusion can be written as:

Since, Y didn't occur< sucrose was not added to the ice cream> X also wouldn't occur<diabetic person wouldn't feel discomfort due to glucose intolerance>.

So, underlying assumption must be:

X is only caused by Y. [/b

OR

X can not be caused by any other way.


Here only answer choice E restates the underlying assumption by refuting the possibility of glucose being already present in ice creams.

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by Target2009 » Mon Jan 24, 2011 3:55 pm
My Pick : E
Negate E : Glucose is naturally present in the ice cream produced by these ice cream companies in amounts large enough to cause discomfort to diabetics who eat this ice cream.

Conclusion "Since there are several ice cream companies who add sucrose to none of the ice cream they produce, diabetics are able to eat ice cream without experiencing discomfort due to glucose intolerance afterward. " is no more holds good.
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by Adam@Knewton » Mon Jan 24, 2011 8:01 pm
Very good responses and discussion, everyone. Most of us seemed to have it down to (D) vs. (E), and the answer is, in fact, (E).

The reason the (D) is wrong is that the argument isn't about just causing discomfort: it's about causing comfort "due to glucose intolerance." Even though (D) would be necessary to show that diabetics don't experience discomfort at all, this is out of scope. As many of you have pointed out, the Negation Test is the best way to approach this question. If you negate (D), it means that there are substances that in fact cause discomfort to diabetics -- but not necessarily substances that are within the scope of this argument (glucose)! On the other hand, if you negate (E), it clearly means that glucose is already present within the ice cream. Note that this doesn't automatically destroy the conclusion (that they won't experience discomfort), but DOES destroy the argument, that not-adding-glucose removes any possibility of them experiencing discomfort, because not-adding-glucose would not mean (if E were negated) that there isn't glucose at all.

Takeaways: 1) Focus on the exact scope of the Conclusion, no further! 2) When using the Negation Test, make sure you're destroying the given argument's logic; 3) Don't be fooled by choices that seem to attack/support the Conclusion but don't address the logic of the Argument!

The winner today, from those who picked (E) correctly, is Stormier, because his explanation best addresses the trap answer, (D), and most neatly, in my opinion, deals with all the other choices. Congrats to Stormier! (his explanation quoted below)

Thanks to everyone else for your contributions. Tomorrow we have our final chapter of the Knewton Verbal Challenge Week, so tune in for it and take your best shot!
stormier wrote:
AdamKnewton wrote: Question 4.

Diabetes is a disease in which the body does not produce or properly use insulin, a hormone that is needed to convert glucose into energy needed for daily life. Because ice cream commonly contains glucose in the form of sucrose, diabetics generally experience discomfort after consuming even a small serving of ice cream. However, since there are several ice cream companies who add sucrose to none of the ice cream they produce, diabetics are able to eat ice cream without experiencing discomfort due to glucose intolerance afterward.


Conclusion - absence of glucose in the ice cream allows diabetics to eat the ice cream without discomfort.

The argument is about discomfort caused by glucose intolerance, and not about discomfort to diabetics caused by other substances.



Which of the following is an assumption on which the argument depends?



(A) These ice cream companies have been able to duplicate the taste of sucrose derived from glucose by means that do not involve adding any potential substances that may be of discomfort to diabetics.

Incorrect. Taste of the ice cream is not relevant to the point of contention. Let's negate the answer choice and say that the ice cream companies have not been able to duplicate the taste by making it diabetic friendly. The argument still holds - because diabetics could still eat the tasteless ice cream and not experience discomfort.

(B) Not all forms of glucose are equally likely to result in this discomfort.

Incorrect. Likelihood of discomfort is not the point at stake. Any form of glucose will cause discomfort according to the premise stated in the stimulus. Thus this answer choice is irrelevant.

(C) Ice cream is not the only food to which glucose is commonly added.

Incorrect. Irrelevant - Whether glucose is added to foods other than ice cream has no bearing on the discomfort that ice cream may cause to the diabetics.

(D) Apart from glucose, there are no substances commonly present in ice cream that would cause discomfort to diabetics.

Incorrect. This is a very tricky answer choice. The argument is about discomfort caused due to glucose intolerance and not about discomfort due to other substances that may be present in the ice cream. This answer choice, although very attractive, is at best irrelevant.

(E) Glucose is not naturally present in the ice cream produced by these ice cream companies in amounts large enough to cause discomfort to diabetics who eat this ice cream.

Correct. Let's negate this choice. Glucose is naturally present in the ice cream produced by these companies in amounts large enough to cause discomfort to diabetics. The argument falls apart. It directly attacks the conclusion - saying that the glucose that is naturally present will cause discomfort to diabetics due to glucose intolerance.
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