According to futuristic writings in the 1960s, robots would soon drast

+1 for (B)
Robots will start harming the gun-holding policemen,who are working for crime reduction too,because robots would not be figure out the difference between criminals and policemen/or anyone else for that matter.

I usually break the arguments apart, seperating the premise from the conclusion.
Concerning the argument you posted i get:
Premise: With night vision and ability to detect the chemicals involved in ballistics, such robots could be programed to paralyze anyone roaming the street at night with a gun: virtually all criminals fit that description. These criminals would be incapacitated and thus unable to resist an easy arrest.
Conclusion: robots would soon drastically reduce crime

So, the only answer choice that could express a flaw in the prediction (the prediction being that "robots would soon drastically reduce crime") is answer choice A, because if the robots are charging at day time and are only effective at night time, then crime rates will consequently increase in day time, weakening the conclusion that "robots would soon drastically reduce crime".

I did not chose B because this answer choice is reffering to the premise of the argument instead of attacking the conclusion.

Nevertheless, I feel I am a bit confused. Could someone please clear this up for me.

tried to Weaken
Conclusion: These criminals would be incapacitated and thus unable to resist an easy arrest.
Premise1: robots could be programed to paralyze anyone roaming the street at night with a gun:virtually all criminals fit that description

(A) Such robots would need to be charged during the daytime.
--> out of scope (charging the robots has nothing to do with Arrests, also robots can work on alternal source of enery such as solar)

(B) Since policemen carry guns, the robots would incapacitate them just as efficiently as they incapacitate criminals
--> correct: should the flow as police also carry guns and robots will not differentiate between police and criminals, as the premise states that "anyone roaming the street at night with a gun"

(C) Because these robots could pose a hazard to cars at night, special barriers would have to be constructed between the paths of the robots and the lanes of traffic.
--> out of scope

(D) It's not obvious that reducing the number of criminals will always be beneficial.
--> out of scope

(E) If the proposal plan were successful, it might ultimate result in a smaller and more efficient police force.
--> this strengthen the conclusion

A) Even if the robots need to be charged during daytime, it still does not affect their effectiveness at night and therefore their ability to reduce crime. INCORRECT.
B) If the robots incapacitate the police (which fights crime), this would aid crime too and put into doubt the assertion that crime would therefore necessarily fall overall. CORRECT.
C) There is no information given in the passage to suggest that building such lanes is a problem, therefore posing no obvious problem for the robots to tackle crime. INCORRECT.
D) Even if this is not beneficial in all manners possible, it will still reduce crime. INCORRECT.
E) We are not discussing the size of the police force here, but the effectiveness of the robots in fighting crime. INCORRECT.

(B) it is.

Premise: Robots can stop criminals that are roaming with a gun at night.
In order to find a flaw, we need to prove that the robots will not help.
Option B just says the same by telling that the robots will incapacitate the policemen too as they also carry guns.
None of the other options even come close.

Correct Option: B

Merged topics. Please, search before posting questions!

I'd think that police officers would stop carrying guns if these robots existed, since there's no obvious reason why they'd need them if all the criminals were incapacitated.

That might be an interesting way to pose the question - instead ask what a likely consequence of the introduction of the robots might be. It seems probable that law enforcement would disarm.

According to futuristic writings in the 1960s, robots would soon drastically reduce crime. With night vision and ability to detect the chemicals involved in ballistics, such robots could be programed to paralyze anyone roaming the street at night with a gun: virtually all criminals fit that description. These criminals would be incapacitated and thus unable to resist an easy arrest.
Type - Flaw
Boil it down - criminals with guns would be incapacitated and thus unable to resist an easy arrest.

(A) Such robots would need to be charged during the daytime. - Irrelevant - we are only concerned about night time
(B) Since policemen carry guns, the robots would incapacitate them just as efficiently as they incapacitate criminals - Correct
(C) Because these robots could pose a hazard to cars at night, special barriers would have to be constructed between the paths of the robots and the lanes of traffic. - Irrelevant
(D) It's not obvious that reducing the number of criminals will always be beneficial. - Irrelevant -
(E) If the proposal plan were successful, it might ultimate result in a smaller and more efficient police force. - Incorrect - we do not need what might happen as a consequence

Answer B

Official Explanation

This bizarre quasi-futuristic scenario is obviously problematic.

(B) is the credited answer, because it speaks directly to the flaw in the argument. Since the robots would incapacitate anyone with a gun at night, they would paralyze both criminals and police officers. Anything that is taking out police officers is not going to be, overall, an effective crime-fighting measure.

(A) & (C) just speak to logistics that could be easily arranged; neither presents a major flaw in the argument.

(D) is a very strange, counter-intuitive statement. Even if we grant the possibility that this statement could be true (that's dubious in and of itself), this would be calling in question the goal of the program, not the logic of the prediction. We are asked, very specifically, would carrying out this plan reduce the number of criminals and fight crime? This statement calls into question the goal --- whether reducing the number of criminals is a desirable end --- which in no way address the logic of the prediction itself.

(E) a "smaller and more efficient police force" does not sound like something inherently bad, so if the plan were successful and this were the result, it's not at all clear that would be at all a problem.

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