Scientist: My research indicates that children who engage in

Answer would be B. Pretty straightforward...

:O this was terrible for me, though i marked B at last by elimination.

In my opinion E is tricky but the answer is B BUT as always:LSAT are not good questions for gmat reasoning. In my opinion

Bumping this LSAT question for those who want the practice!

Can someone help on this. I did not get why B is the answer

nightblade354 gmatexam439 SonalSinha803 GMATNinja abhimahna

warrior1991,

Please find suitable explanations here:

Powerscore: https://forum.powerscore.com/lsat/viewtopic.php?t=1483
Manhattan LSAT: https://www.manhattanprep.com/lsat/foru ... -t785.html

Let me know if you need further clarification!

Hi may be in can help ,

Here is the argument with all the choices.

Scientist: My research indicates that children who engage in impulsive behavior similar to adult thrill-seeking behavior are twice as likely as other children to have a gene variant that increases sensitivity to dopamine. From this, I conclude that there is a causal relationship between this gene variant and an inclination toward thrill-seeking behavior.

Which one of the following, if true, most calls into question the scientist's argument?

A) Many impulsive adults are not unusually sensitive to dopamine.

B) It is not possible to reliably distinguish impulsive behavior from other behavior.

C) Children are often described by adults as engaging in thrill-seeking behvaior simply because they act impulsively.

D) Many people exhibit behavioral tendencies as adults that they did not exhibit as children.

E) The gene variant studied by the scientist is correlated with other types of behavior in addition to thrill-seeking behavior.

OA is B.

This is weaken the argument question. We can weaken the argument in many ways namely: Show that the conclusion does not follow from the premises, discredit any premise of the argument, discredit the assumption of the argument.

Now coming on to this question we have a very real phenomenon going on today i.e. https://www.rxlist.com/antibiotic_resis ... dition.htm

A is out of scope. This choice may be true but this information does not help us in the case of children.

B correct. One way to destroy the argument is to question the sample space or the statistics used in the argument. Here the methodology to classify various types of behavior is questioned and if this is indeed true then we have serious doubts to take the conclusion as true. Hence this option weaken the argument.

C Is just information from the passage and again offers no conclusive information to doubt the conclusion.

D This choice is out of scope as there are always people who would deviate from the said behavior that they did not display in their childhood. They may have been coy or introvert in their child hood but now as adults they have become extrovert and daring. So it can not establish casual relationship discussed in the argument.

E Again this may be true but we are concerned with only thrill seeking behavior. So again out of scope.

Thanks nightblade354 and arvind910619

Found this one quite challenging...

Could someone add the LSAT tag?

Arro44,

Good catch. I thought I tagged this one, considering I posted two LSAT links. Oh well.

the study part is presented as apremise for the argument. In option B arent we challenging a premise??
I know that we can doubt on the methodolgy, could anyone please tell me as to how far we are supposed to doubt a premise?? and at what point dooubting the premise would be wrong??
Thankyou

AdityaHongunti: I don't think so. The premise tells about a research conducted by a scientist. In the answer choice, in option B, we are accepting the research, but doubting the sample size. or in other words, we are doubting the methodology. I think as long as we are not altering any given facts, we are okay. Experts can answer more clearly.

Regards,
Arup

Does not OA(B) doubt the validity of the premise?
My research indicates that children who engage in impulsive behavior similar to adult thrill-seeking behavior are twice as likely as other children to have a gene variant that increases sensitivity to dopamine

Generally, in weaken questions, we can challenge an assumption (link between premise and conclusion).

AjiteshArun , GMATNinja , MagooshExpert , GMATGuruNY , VeritasPrepBrian , MartyMurray , DmitryFarber , VeritasKarishma , generis , other experts - please enlighten

Skywalker18 and AdityaHongunti ,

The LSAT and GMAT differ in this area.

GMAT almost never attacks the premises.

The LSAT attacks the premises more frequently than the GMAT does.

• I suspect that the GMAT does not offer attacks on premises very often because
an attack on a premise is too "easy."

• That is, spotting a weak premise that then weakens the conclusion is not very difficult.
-- If a premise is weakened, we merely must:
1) compare any answers we have not eliminated, and
2) be sure that the weakened premise indeed weakens the conclusion
(I am hedging a bit in this sentence. Sometimes the way that a premise is weakened on the LSAT is not enough to kill the conclusion.)

You are both correct.

Answer B attacks the premise. Further, Answer B effectively attacks the premise.

-- AdityaHongunti wrote: In option B arent we challenging a premise??
Yes. The premise is faulty.
-- Skywalker18 wrote: Does not OA(B) doubt the validity of the premise?
Yes. The premise is not valid.

If we weaken a premise, then we will probably weaken the conclusion.

• Effectively attacking the premise

Scientist: My research indicates that children who engage in impulsive behavior similar to adult thrill-seeking behavior are twice as likely as other children to have a gene variant that increases sensitivity to dopamine. From this, I conclude that there is a causal relationship between this gene variant and an inclination toward thrill-seeking behavior.

If a child engages in impulsive behavior [similar to ABC],
that child is more likely to have a gene variant.
That gene variant increases sensitivity to dopamine. (Let's call that gene variant "D")

[Assumed, tacit, or implied. Not stated]:
Because impulsive behavior in children is similar [enough] to thrill seeking behavior in adults [that characteristics of these children will be present in those adults],*
and because impulsive behavior in children often indicates the presence of gene D,
I conclude that IF thrill-seeking behavior exists (result), then gene D is present (cause)

Option B effectively attacks the premise: It is not possible to reliably distinguish impulsive behavior from other behavior.

It is NOT POSSIBLE (wow - strong) to reliably distinguish impulsive behavior from other behavior.

• NOT POSSIBLE to identify "impulsive" = any conclusions drawn from any group labeled impulsive are not valid

Bad methodology: she cannot distinguish impulsive from non-impulsive behavior in children. Her group is random.
The "impulsive" group she has gathered can't even be called an "impulsive" group.
It's a collection of children. The end.

Being able to identify "impulsive" children is foundational to her later claim

She has chosen a group of what SHE says are IMPULSIVE children who are more likely to have some gene, D.
From that group, she has assumed quite a bit and concluded something.

But her methodology is bad.
Answer B says that she cannot truly identify impulsive children.

She does not even "get off the ground."
"Impulsive" does not mean anything. It is not possible to identify impulsive.

Conclusion smashed.

• Takeaway

Takeaway: although very rare on the GMAT, IF you see an answer that attacks a premise,
and it is the only answer that weakens the conclusion, choose it.

Hope that helps.

*The Trap in THIS question: the assumption that "impulsive kids = thrill seeking adults." IRRELEVANT

In the background is the assumed similarity between impulsive behavior and thrill-seeking behavior.

The scientist says that she has examined a specially chosen population: children who behave impulsively.

From her observation of those children, who are likely to have gene D,
she draws a conclusion about adult thrill-seeking behavior
based on a vulnerable assumption that impulsive in children = thrill-seeking behavior in adults.

The words in pink above are what the GMAT would usually go after.

Given the answer choices in this question, those words are irrelevant. We don't get that far in the argument,
because she is NOT CAPABLE of choosing, accurately, children who are impulsive.

I was between A and B but I think that A is irrelevant because thrill-seeking behavior in adults is not described as "impulsive". If we have replaced "impulsive" with "thrill-seeking", choice A would have been better.

Posted from my mobile device

A) Many impulsive adults are not unusually sensitive to dopamine.
This doesn't rule out the possiblity some may be sensitive

B) It is not possible to reliably distinguish impulsive behavior from other behavior.
This will completely ruin the scientists plan if all the base point he used for projection itself was wrong

C) Children are often described by adults as engaging in thrill-seeking behvaior simply because they act impulsively.
May be we are not aware about the size of the children and adult hence we cannot generalize

D) Many people exhibit behavioral tendencies as adults that they did not exhibit as children.
This doesn't rule out the possiblity some can act impulsively

E) The gene variant studied by the scientist is correlated with other types of behavior in addition to thrill-seeking behavior
Throughly out of context
Hence IMO B

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