We can now dismiss the widely held suspicion that sugar consumption

Question

We can now dismiss the widely held suspicion that sugar consumption often exacerbates hyperactivity in children with attention deficit disorder. A scientific study of the effects of three common sugars—sucrose, fructose, and glucose—on children who have attention deficit disorder, with experimental groups each receiving a type of sugar in their diets and a control group receiving a sugar substitute instead of sugar, showed no statistically significant difference between the groups in thinking or behavior.

Which one of the following, if true, would most weaken the argument above?

(A) Only one of the three types of sugar used in the study was ever widely suspected of exacerbating hyperactivity.
(B) The consumption of sugar actually has a calming effect on some children.
(C) The consumption of some sugar substitutes exacerbates the symptoms of hyperactivity.
(D) The study included some observations of each group in contexts that generally tend to make children excited and active.
(E) Some children believe that they can tell the difference between the taste of sugar and that of sugar substitutes.

piyushluniya · Accepted Answer

C is the Answer.
 Reasoning : 
if the sugar substitute also exacerbates hyperactivity, then both subjects of the study will depict same behavior.
So, the study will show no difference.
But, in such case we cannot conclude that sugar didn't exacerbated hyperactivity.

For Ex : A Study was conducted to show that People didn't get cold after Eating Ice cream. So, one group was given ice cream and another was given a cold-drink. Now, if both group got cold, then we cannot say that because eating ice cream depicted same behavior as drinking Cold-drink, ice cream consumption doesn't make people catch cold.

Hope this helps.
Thanks

agrasan · Answer

Hi  KarishmaB   MartyMurray

I don't understand how (C) is correct, here is my logic to eliminate (C). Please let me know what's wrong with that.

(C) The consumption of some sugar substitutes exacerbates the symptoms of hyperactivity.
This is not a weakener as we don't know whether the sugar substitute mentioned in the argument is a part of these  "some sugar substitutes".  It is natural that out of 100 sugar substitutes, "some" like 8-10 sugar substitutes exacerbate the symptoms. I followed the principle that Weaken answer choices are usually wrong precisely because they use weak language like "some," which may or may not apply to the stimulus.

Please let me know what I am thinking wrong here.

guddo · Answer

Here is a solution from Power Score, which might be helpful:

Complete Question Explanation

Weaken. The correct answer choice is (C)

This stimulus discusses the impact of sugar consumption on hyperactivity in children with ADD (attention deficit disorder). The stimulus begins with the author’s conclusion: We can now dismiss the notion that sugar consumption exacerbates hyperactivity in ADD children. This conclusion is based on a “scientific study” (be wary of the vague appeal to authority here) which showed that hyperactivity levels among ADD children who were given three common sugars was not distinguishable from those of ADD children who received a sugar substitute (we should also note the vague description of the sugar substitute—its effects must be distinguishable from those of sugar for it to facilitate an effective control group).

The question stem asks which of the answer choices most weakens the argument.

Answer choice (A): The fact that only one of the sugars used in the study was widely suspected of exacerbating hyperactivity does not change the observed behavior of the study’s subjects. This does not weaken the conclusion drawn in the stimulus.

Answer choice (B): Since the stimulus is concerned exclusively with ADD children, information about children in general is not relevant to the argument.

Answer choice (C): This is the correct answer choice.    If the sugar substitute used in the study had the same or similar effect as the three sugars, it would not facilitate a good control group for the study, and no conclusions about distinguishing characteristics of the sugars could be logically drawn.

Answer choice (D): As long as all groups participated in these activities, it would not affect the outcome of the study (of course if the control group participated in these activities but the sugar groups did not, the study would be severely flawed).

Answer choice (E): The fact that some children have this belief would not necessarily have an effect on this study, as it is unclear whether any of the subjects would have actually been able to make this distinction, nor whether such knowledge would have had any effects on their behavior.

guddo · Answer

Also, your elimination is based on a rule that does not apply here.

In weaken questions, “some” can be plenty strong if it creates a  realistic  alternative explanation for the study’s result. Choice (C) does exactly that: it says that sugar substitutes can increase hyperactivity. If the control group’s substitute happened to be one of those, then the control group would look more hyperactive than it should, which could erase the difference between the sugar groups and the control group. That undermines the argument’s inference from “no difference” to “sugar does not exacerbate hyperactivity.”

Also, you are treating “we don’t know if it’s the same substitute” as a reason to reject it. But these questions are conditional: if (C) is true, then it raises a plausible flaw in the study’s control condition, which is enough to weaken the conclusion.

MartyMurray · Answer

We can now dismiss the widely held suspicion that sugar consumption often exacerbates hyperactivity in children with attention deficit disorder. A scientific study of the effects of three common sugars—sucrose, fructose, and glucose—on children who have attention deficit disorder, with experimental groups each receiving a type of sugar in their diets and a control group receiving a sugar substitute instead of sugar, showed no statistically significant difference between the groups in thinking or behavior.

Conclusion of the argument:

We can now dismiss the widely held suspicion that sugar consumption often exacerbates hyperactivity in children with attention deficit disorder.

Support for the conclusion:

A scientific study of the effects of three common sugars—sucrose, fructose, and glucose—on children who have attention deficit disorder, with experimental groups each receiving a type of sugar in their diets and a control group receiving a sugar substitute instead of sugar, showed no statistically significant difference between the groups in thinking or behavior.

We see that the reasoning of the argument is basically the following:

Since children who consumed sugar behaved and thought similarly to children who consumed sugar substitutes instead, sugar must not exacerbate hyperactivity.

Which one of the following, if true, would most weaken the argument above?

This is a Weaken question, and the correct answer will indicate that, even though the supporting facts are true, the conclusion may not be.

(A) Only one of the three types of sugar used in the study was ever widely suspected of exacerbating hyperactivity.

This choice basically indicates that two types of sugar were not suspected of exacerbating hyperactivity.

The fact that two types of sugar were not even suspected of exacerbating hyperactivity certainly does not weaken the case for the conclusion that sugar does not exacerbate it.

Now, if this choice said that there are other types of sugar, which are suspected of exacerbating hyperactivity, that were not used in the study, then it would weaken the argument. It doesn't says that though. It just says something meant to sound that way and potentially fool us.

Eliminate.

(B) The consumption of sugar actually has a calming effect on some children.

The fact that sugar has a calming effect on some children is in line with the conclusion that sugar does not exacerbate hyperactivity.

So, this choice basically does the opposite of what the correct answer must do.

Eliminate.

(C) The consumption of some sugar substitutes exacerbates the symptoms of hyperactivity.

This choice is interesting.

After all, if this choice is true, then it's possible that the reason why the children in the two groups acted similarly was not that neither sugar nor sugar substitutes cause hyperactivity but rather that both DO cause hyperactivity.

After all, if consumption of some sugar substitutes exacerbates the symptoms of hyperactivity, then it could be that the children in both groups were caused to be more hyperactive, the ones that consumed sugar by the sugar, and the ones that consumed sugar substitutes by the substitutes.

Now, do we know for sure that the sugar substitute consumed by the children observed was in fact one of the "some" that exacerbate hyperactivity? No, we don't. At the same time, since the sugar substitute consumed could have been one of those, the information provided by this choice casts doubt on the case for the conclusion, and that's all a Weaken correct answer has to do.

Keep.

(D) The study included some observations of each group in contexts that generally tend to make children excited and active.

This information doesn't clearly weaken or strengthen the case for the conclusion.

After it simply mentions one type of context in which all the children were observed.

If the contexts in which the two groups were observed had been different, then that information could have weakened the argument by introducing a confounding variable, but this choice doesn't do that.

We could argue that, if this choice said that the study included ONLY observations of children in contexts that tend to make children excited, then we could presume that it could have been difficult to tell whether the the children acted similarly simply because they were all so exited by the contexts that what they had consumed made little difference, a fact that could have made the study results suspect. This choice doesn't say that either though.

Eliminate.

(E) Some children believe that they can tell the difference between the taste of sugar and that of sugar substitutes.

What children believe about the tastes of sugar and sugar substitutes has no clear relationship with the effects of these substances on behavior when consumed.

Eliminate.

Correct answer:   C

We can now dismiss the widely held suspicion that sugar consumption

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We can now dismiss the widely held suspicion that sugar consumption

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