Over the past few years, violent crime has decreased dramatically in

Question

Over the past few years, violent crime has decreased dramatically in City X. During this period, there has also been an increase in the number of late-night street vending licenses granted by the city, thereby increasing the number of people on the streets at night. Therefore, the reduction in violent crime must be related to the increase in vending licenses.

Which of the following, if true, most seriously casts doubt on the argument above?

(A) The amount of nonviolent crime in City X has not changed much over the past few years.
(B) A reduction in crime also causes more pedestrians to be out on the streets in the evenings.
(C) The number of street vendors in City X has increased steadily during the period in question.
(D) During the past few years, City X has reduced the amount of city taxes street vendors must pay.
(E) Last year, City X increased the number of police officers working at night.

pzgupta · Answer

A -  INCORRECT  - Since non-violent crimes aren't what the argument is talking about
B -  INCORRECT  - We need to find something that weakens the conclusion - decrease in v crime is due to increase in vending licenses. 
C-  INCORRECT  - Irrelevant
D -  INCORRECT  - Irrelevant. This would cause more vendors on the street but probably supports the conclusion a little instead of weakening it.
E-  CORRECT  - Provides an alternative reason for why the crimes might have reduced. This would cast doubt on the conclusion that the decrease in v crime is due to increase in vending licenses.

sunny91 · Answer

shobhitkh , kindly reconfirm the OA. Option E is talking about only last year, whereas the stimulus talks about few years. I think the answer could be C.

J2S2019 · Answer

I have a concern here
 GMATNinja , could you please help me out to figure if my reasoning is correct here?

This is a causal argument, when we figure out X is the cause of Y in a argument (here increase in people at night - decrease in violent crimes)

To weaken such a conclusion, we have basically 3 options

1> to support alternative cause of the effec
2>if the reverse, i.e, the effect has not caused the cause
3>the timeline difference, basically cause has happened before the effect

Now if we go with the option 1> then the answer is pretty straight forward E
but if we analyze the argument in light of option 2> - then why cant B be the answer

Need your expert reply here. Kindly help.

vicky2019 · Answer

I think C is a better option bcz it says not because of increased presence of people there is a reduction in violet crimes but it is in fact the opposite( reduction in crimes led to increase in increased presence of people. So there must be another reason for reduction in violent crime rates.)

E says that there is an increase in number of police officers working at night in the last year. But the crimes have been going down from the past few years.

IMO C. Please correct me if my reasoning is wrong.

Aviral1995 · Answer

VeritasKarishma   jennpt   AjiteshArun 
I am really confused b/w D and E
I considered D because this might be the alternate reason why vendors increased
However in OA-E it talks about just last one year, how E can be the answer

sid0791 · Answer

egmat   VeritasKarishma

Can you please help me with this?
I am confused as, why E should be the OA, it is talking about last year. And according to the argument, crime rates are decreasing for the past few years.

KarishmaB · Answer

sid0791 
 Aviral1995

I wouldn't invest too much time in this question.

(E) does give an alternative reason but with 'last year' it isn't valid. It doesn't explain dramatic decrease of "past few years" 
Also, the conclusion  "the reduction in violent crime must be related to the increase in vending licenses."  just says that the two are related. Which one causes the other isn't given. Decrease in crime could make late-night business more viable and more people at night could lead to decrease in crime.
That said, the argument does seem to be suggesting that more people at night is the reason crime has decreased else there was no need to mention  "...thereby increasing the number of people on the streets at night"

If we assume that the author is trying to say that more vendors caused decrease in crime, then (B) helps.

(B) A reduction in crime also causes more pedestrians to be out on the streets in the evenings.

Tells us the relation is the other way around.

But the conclusion just says "they are related" so if we were to assume that the author just meant that they are related, then (E) would have made sense but with "last few years".

As for (C) and (D), in any case they are wrong.

(C) The number of street vendors in City X has increased steadily during the period in question.

A relation need not be proportional. Perhaps vendors increased steadily but crime decreased dramatically.

(D) During the past few years, City X has reduced the amount of city taxes street vendors must pay.

This introduces a new variable "city taxes" which impacts "number of vendor licenses". But it doesn't strengthen or weaken the relation between "number of vendor licenses" and "crime".

sid0791 · Answer

VeritasKarishma

I choose A,

Although at first read, I discarded it, my reasoning to discard others were-

B- reduction in crime is causing pedestrians to come out, it doesn't help to change the fact that crimes have reduced, and according to the argument, the reason is because of vendors, nothing to weaken it.

C- it basically strengthens the argument

D- No relation

E- 'Last year', this was the main reason for discarding it.

Although I thought of another reason, that if crimes are reduced for past few years, and 'Last year' police officers have been increased, then it means that there could be some other relation, that why crimes are getting reduced. Because for the past few years vendors are getting increased.

But this reason can only be concluded if we know for a fact that police officers were increased only to reduce crime.

I discarded this option because there could be other reasons as well for police officers to increase.

Thus I was left with A, and somehow it makes sense as well, although the argument doesn't ask for non-violent crimes, if non-violent crimes are increasing, then there could be some other reason for violent crime decreasing such as harsh punishment, etc.

Thanks
Siddharth

sony1000 · Answer

Veritaskarishma , thanks for the explanation but I do not comprehend which is the right answer and why.

sahilcisco · Answer

what crap question! the argument talks about over the past few years and the answer talks about last year.

ShubhamA · Answer

Choice C seems closer than choice E. Time-frame provided in E is irrelevant proposition for reduction in crimes (deputed officers since last year) whereas Choice C states about subtle change in number of street vendors comparing to drastic change in number of crimes. So there must be some other reason to stamp the assertion.

radhika2055 · Answer

what does cast a doubt here means does it means weaken the argument and if it means so then how can it be E?

Gylmitul · Answer

Hi Karishma

So, are you saying that the answer choices are weak/flawed. Cause I too got confused between E and B and ruled out E because I considered the "last year" error to be more a definitive error.

CrackverbalGMAT · Answer

Hi Radhika

You are right - "cast a doubt" does indeed mean "weaken"

In this argument, the conclusion drawn is that reduction in violent crime is due to the increased vending licenses provided. Option (E) provides a potential alternate explanation for the reduction in crime ie; it could be due to the increased number of police officers patrolling at night. Therefore, option (E) weakens the argument (in other words, the conclusion) that the reduction in crime is due to the increased vending licenses.

Hope this helps.

arbazfatmi1994 · Answer

My answer is B - A reduction in crime also causes more pedestrians to be out on the streets in the evenings.

Why?

Cause-effect relation. If a reduction in crime causes more pedestrians to be out, then people are out because of less crime, and not because of the increase in the number of vendors. Hence, the reduction in crime might not be related to the number of vendors.

What is wrong with option E? - Crime has reduced over the past few years, while the number of policemen have only increased since last year

Over the past few years, violent crime has decreased dramatically in

Prep Toolkit

Top 5 GMAT Debrief Videos

615 to 715 in 15 Days (Ria's Strategies)

More than Quant/Verbal Abilities: Speed vs. Accuracy

745 with Only Self-Prep and GMAT Club

From 555 to 765: 210-point Improvement

Perfect 805 Score Debrief by Julia

My Rewards

GMAT Critical Reasoning (CR) Questions

Over the past few years, violent crime has decreased dramatically in

Prep Toolkit

615 to 715 in 15 Days (Ria's Strategies)

More than Quant/Verbal Abilities: Speed vs. Accuracy

745 with Only Self-Prep and GMAT Club

From 555 to 765: 210-point Improvement

Perfect 805 Score Debrief by Julia

My Rewards