The number of airplanes equipped with a new anti-collision device has

Question

The number of airplanes equipped with a new anti-collision device has increased steadily during the past two years. During the same period, it has become increasingly common for key information about an airplane’s altitude and speed to disappear suddenly from air traffic controllers’ screens. The new anti-collision device, which operates at the same frequency as air traffic radar, is therefore responsible for the sudden disappearance of key information.

Which one of the following, if true, most seriously weakens the argument?

A. The new anti-collision device has already prevented a considerable number of mid-air collisions.

B. It was not until the new anti-collision device was introduced that key information first began disappearing suddenly from controllers’ screens.

C. The new anti-collision device is scheduled to be moved to a different frequency within the next two to three months.

D. Key information began disappearing from controllers’ screens three months before the new anti-collision device was first tested.

E. The sudden disappearance of key information from controllers’ screens has occurred only at relatively large airports.

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foookato · Answer

IMO D , its obvious becuz A has does nothing, B strengthens, C does nothing, E does not do the job entirely as in large airports maybe the new tech is resposnible for key info disappearing. LMk thoughts

IrascibleDoctor · Answer

Ans is D the author assumes that the two events taking place at the same time, one is causing the other. hence to waken it we can find an alternate which breaks this causality , this is provided by ans D as disappearence is prior to the intro of device suggests some other possible cause of this!

NextstopISB · Answer

Restating the Argument: 
The argument claims that the new anti-collision device is responsible for key information about airplanes disappearing from air traffic controllers' screens because: 
1. The number of airplanes equipped with the device has steadily increased in the past two years. 
2. The disappearance of key information has become more common in the same period. 
3. The device operates at the same frequency as air traffic radar.

To weaken this argument, we need to show that something other than the new device is causing the issue.

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Examining Each Answer Choice:

A. The new anti-collision device has already prevented a considerable number of mid-air collisions. 
Incorrect because: 
- This option talks about the effectiveness of the device in preventing collisions, which is unrelated to the argument. 
- The argument is not about whether the device is useful but whether it is causing information to disappear. 
- The fact that the device prevents collisions does not mean it does not interfere with air traffic control screens.

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B. It was not until the new anti-collision device was introduced that key information first began disappearing suddenly from controllers’ screens. 
Incorrect because: 
- This actually strengthens the argument instead of weakening it. 
- If the disappearance started only after the device was introduced, it suggests a cause-and-effect relationship. 
- We are looking for a way to break that connection, not reinforce it.

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C. The new anti-collision device is scheduled to be moved to a different frequency within the next two to three months. 
Incorrect because: 
- This talks about future actions, not about whether the device caused the problem in the past or present. 
- Even if the frequency will change in the future, it does not disprove the claim that the device is causing issues now.

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D. Key information began disappearing from controllers’ screens three months before the new anti-collision device was first tested. 
Correct because: 
- This directly weakens the argument by showing that the problem existed before the device was introduced. 
- If key information was already disappearing before the device was in use, then the device cannot be the cause of the problem. 
- This breaks the cause-and-effect assumption made in the argument.

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E. The sudden disappearance of key information from controllers’ screens has occurred only at relatively large airports. 
Incorrect because: 
- This does not disprove that the anti-collision device is responsible. 
- Even if the problem happens only at large airports, the device could still be the cause.

Ans D

Bunuel · Answer

OFFICIAL EXPLANATION

The correct answer choice is (D)

The stimulus commits the classic error of assuming that because two events occur simultaneously that one must cause the other. The phrase used to indicate the causality is “responsible for.” D = anti-collision device, SD = sudden disappearance of key information, DSD. The question stem asks you to weaken the argument, and according to the “How to Attack a Causal Conclusion” section you should be on the lookout for one of several primary methods of attacking the argument.

Answer choice (A): This answer presents another effect of the cause, but this additional effect does not weaken the argument. To analogize this answer to the argument, imagine a scenario where a speaker concludes that playing football makes a person more prone to sustaining a leg injury. Would suggesting that playing football makes a person more prone to a head injury (another effect) undermine the first statement? No.

Answer choice (B): This is an Opposite answer that supports the conclusion. By showing that the key information did not disappear prior to the appearance of the anti-collision device, the argument is strengthened because the likelihood that the device is at fault is increased.

Answer choice (C): This information has no effect on determining if the device causes the information to disappear from the screen because it references an event that has yet to occur.

Answer choice (D): This is the correct answer , and this answer falls into the third category for weakening a causal argument: “Show that although the effect exists, the cause did not occur.” In this instance, the effect of information disappearing from the screen occurred prior to the creation of the supposed causal agent, the anti-collision device.

Answer choice (E): This answer choice has no impact on the argument. We cannot make a judgment based on the size of the airport because the argument did not mention airport size or anything directly related to airport size.

The number of airplanes equipped with a new anti-collision device has

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The number of airplanes equipped with a new anti-collision device has

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