According to a recent report published by the Crime Bureau

Question

According to a recent report published by the Crime Bureau, the number of murders in the city has increased by over 20% in the last year over the previous year. One way to rein in the rising murder rate is by holding authorized gun dealers responsible for selling weapons to individuals with criminal records. Clearly, if these dealers are more selective while selling guns, there will be a significant decline in the number of fatalities.

Which of the following statements makes the argument invalid?

A.Individuals without criminal records commit murders.

B.Authorized gun dealers cannot differentiate between individuals with and without criminal records.

C.Gun dealers are driven only by profit maximization motives.

D.Almost in all the murders in the city, a gun is the weapon used to commit the crime.

E.Current laws do not regulate the sale of dangerous weapons such as guns in the city.

sobby · Answer

Torn between A and B ..
Selected A finally..

Posted from my mobile device

emockus · Answer

Torn between A and B, ended up selecting B. The argument is based on the gun store owners being selective. Choice "A" doesn't deal with the gun owner being more selective as to whom guns are sold to. Only answer choice "B" deals with the gun store owner having to be selective.

"Individuals without crime records commit murders" - this does not deal with the gun store owner having to be selective.

"Individuals without crime records commit murders" - this does not deal with the gun store owner having to be selective.

pushpitkc · Answer

Clearly, the conclusion of the argument is 
  if these dealers are more selective while selling guns, there will be a significant decline in the number of fatalities.

Of the available answer choices, Choice C,D and E are irrelevant to say the least.
Option A is a generic statement which is not closely linked to the conclusion and hence cannot make the argument invalid.
 Option B,  if negated can smash the conclusion and hence render the argument invalid and is hence, the correct choice

TheMechanic · Answer

Why not D? If we negate D - None of the crimes committed in the city are committed with a gun. Hence even if the authorized gun seller discriminates the people based on the criminal records, there wont be any impact on the Crime rate. 
Please clarify this.

daboo343 · Answer

I think B must be the answer
argument says
More selective--- decline in fatalities
Option B says dealer don't have the ability to select

Lucy Phuong · Answer

Hi, I would like to give some thoughts. Hope you find it helpful. First of all , negation technique is highly recommended for assumption questions , not other types of questions. Second , just read your reasoning again. You are treating this question as an assumption, aren't you? (With an assumption question, an option is correct when its negation totally destroy the solution). Yes, that reasoning should be applied to assumption type only. In fact, however, this is a weaken question. Lastly , well I think your negation for option (D) is not correct. This is original option (D): D.Almost in all the murders in the city, a gun is the weapon used to commit the crime. Intuitively, "almost" usually refers to a number larger than 50%. For example, your team has 3 tasks of equal workload, one of which is assigned to you. Can u say that u are responsible for almost team's tasks? No! Therefore, negation of option (D) should be: In no murder / in a few murders in the city, a gun is the weapon used to commit the crime. 2 above cases of negations can result in different results, as follows: "In no murder in the city, a gun is the weapon used to commit the crime." --> No murderer uses guns, then the proposal will not cut down the number of fatalities. "In a few murders in the city, a gun is the weapon used to commit the crime." --> Some murderers, though not many, use guns to commit crime. Therefore, the initiative targeting individuals with criminal records can lead to a decline in the number of fatalities. Should u have any concern, just response

smitsharma · Answer

One way to rein in the rising murder rate is by  holding authorized gun dealers  responsible for selling weapons to individuals with criminal record s. 
Option A is not relevant because if individuals without criminal records commit murders, then, according to the argument, the dealers cannot be held responsible for selling weapons to the murderers. (since, the murderers did not have a criminal record prior to the murders)

Hence,  B

Lucy Phuong · Answer

My reasoning to eliminate option (A)

A. Individuals without criminal records commit murders.

(A) is totally irrelevant, because the option focuses on "Individuals without criminal records", while the proposal deals with gun usage of individuals with criminal records. They are 2 distinct groups. It does not matter whether the proposal can reduce number of non-criminal record people, because after all, what we care is whether the initiative can help prevent people with criminal records from using guns.

For examples: 
In order to cut down student's number of hours spent on video games, teachers suggest that male students engage in weekly social activities. The argument "female students play video games" does not have any impact on viability of the teachers' idea. Girls play video games, so do boys. If some boys spend less time playing, the total number of students' hours on video games will decrease accordingly.

Only if someone argues "ONLY female students play video games", then yes, the initiative will be likely to lose its ground.

FB2017 · Answer

If Option B is true then there is no means to prevent the crime by using guns, however the option A also assumes individual without criminal records commit murder then how would the conclusion authorize drawn on gun sellers being seelctive about the customers without crime records be considered valid or effective.

Firdaus · Answer

GMATNinja 
which one of the following choices make the argument invalid?
- In above replies, discussion has been about the assumption. Dont the question stem asks to make argument invalid/weaken?

Option D - It looks like assumption.
Option B - Weakens - correct choice.

Can you please help?

profileusername · Answer

There are multiple assumptions within the OA for this question, not to mention several more assumptions in the stem that go unaddressed.

1. Individuals with past criminal record are more like to have contributed to this crime increase.
2. The percentage increase in the murders is actually not only a proportional increase within the total crime number.
3. Guns are mostly used for the past murders and also in the murders in that 20% increase range.

Option B takes for granted that it is indeed individuals with criminal records that have been significantly more responsible for the past murders and also the murder increase. In my opinion, this is not an air-tight assumption question stem. There has to be a statement in the stem that provides support to taking this fact about individuals with past criminal records for granted. Then, option B would make more sense.

Correction: This is question was stored in the "assumption" question type category. Thus, the analysis given above is from the perspective of considering this question an assumption question.

roadrunner · Answer

Torn between A and B. I think both choices to a varying degree weakens the argument.

However, in reviewing both choices, I could come up with few situations in which A will not weaken the argument as much as B does.
1. how did these individuals committed murders? Gun, knife, martial arts?
2. How much do these individuals contribute to the increase in number of murders? 1%, 10%, 60%?

IMO B

srikanth9502 · Answer

A) What percentage of people commiting murders have criminal records?
If only 1% of the people commiting murders do not have criminal records,  the conclusion is valid , because if you avoid selling weapons to 99% of the people commiting murders i,e having criminal records, the murder rate can be drastically reduced. On the other hand, if 99% of the people commiting murders are the ones who do not have criminal record, then the conclusion does not hold true, because, we are avoiding the sale of the weapons to only 1% of the criminals.
Hence Option A is incorrect due to dual possibilty.

B) Destroys the conclusion. If the owners are unable to differentiate between two categories, there is no point in telling them to be selective.

chesstitans · Answer

what is the source of this question?
B is correct b/c it directly links with the argument.

manigarg · Answer

Its already given as premise that authorized dealers should be responsible for selling weapon to person with criminal record.( assuming premises goes unchallenged in GMAT). Also acc. to conclusion=> significant decline will occur in nu. of fatalaties by doing so..... 
Now to weaken this we can take into account individuals who did not have criminal record because such people can still keep a good number of murders.

ravi546 · Answer

Why not option E can be considered? Because, if the laws cannot regulate the sale of guns, then the conclusion that gun sellers' responsibility is nullified right?

Chandrahaskrishna · Answer

Hey...
I have read almost all the explanations, and I thought I will offer mine as well.
I was down to A and B, just as a lot of people were.
I was swinging towards B, and I thought that I should look critically at A, so that I can trump the same.
So here is what I thought about A.
Option A says that 'Individuals without criminal records commit murders'.
The conclusion of the argument is to reduce the murders. However, A just talks about the murders being committed. We do not know whether 'Individuals without criminal records commit MORE murders or LESS murders'. So in the absence of this information, and with a better answer option, which ties exactly back to the scope of the argument - Gun dealers - , I think that B is a better choice to pick.
Correct me if I am wrong.

Regards

Mavisdu1017 · Answer

Hello expert,
I think both A and B can weaken the argument from different aspects. A is an alternative cause which justifies the method not achieves its goal (but we don’t know the proportion of murders committed by people who are not with criminal records; if this proportion is very low, maybe achieve the goal?) , while B explains why the method not makes its goal come true from the feasibility of the method.
But I don’t know how to compare their degrees of weakening, would you like to share some your opinions? Thanks.

MartyTargetTestPrep · Answer

This question isn't great for just the reason you have highlighted: what (A) says is not clear. Does it mean that all murders are committed by people without criminal records? Some are? A few are? If all murders are committed by people without criminal records, then the plan will not work. If only a fraction of murders are committed by people without criminal records, then the plan may work.

So, how can we answer this question?

Well, (B) for sure destroys the plan.

On the other hand, (A) can be read as indicating that some murders are committed by people without criminal records, while others are committed by people with criminal records. In that case, the plan could still result in a decline in fatalities.

So, since (B) for sure destroys that plan, and (A) can be read in a way in which the plan works, we can go with (B).

According to a recent report published by the Crime Bureau

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According to a recent report published by the Crime Bureau

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