Logical Reasoning

PT109 · S1 · Q25 The number of airplanes equipped

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The number of airplanes equipped with a new anticollision device has increased steadily during the past two years.

Conclusion

The new anticollision device is responsible for the sudden disappearance of key information from air traffic controllers' screens.

Evidence

The number of airplanes equipped with a new anticollision 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 anticollision device operates at the same frequency as air traffic radar.

Evaluate

This argument presents a correlation between two events: the increase in airplanes equipped with the new anticollision device, and the increased disappearance of key information from controllers' screens. The author concludes causation; the device is causing the loss of information.

Curious Fact

Why is key information suddenly disappearing from controllers' screens?

Author's Explanation

The new anticollision device is causing the disappearance because it operates at the same frequency as air traffic radar.

We can strengthen the argument by increasing the plausibility that the device is causing the interference or weaken it by offering alternative explanations for the missing information or by disputing the idea that the device operating at the same frequency causes this interference.

Goal

Let's find an answer that suggests an Alternate Explanation for the disappearing information or disputes the causal link between the anticollision device and disappearing information.

25.

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

The new anticollision device has
No Impact
The fact that the device prevents collisions doesn't affect whether it causes disappearance of key information from screens.
2% picked this
It was not until the
No Impact
If key information began disappearing only after the device was introduced, it supports the idea that the device could be involved, not weakens it.
4% picked this
The new anticollision device is
No Impact
This choice describes a plan to change frequency, but it does not address the current causal relationship claimed in the argument.
1% picked this
Correct
Key information began disappearing from
Why this is right
If key information began disappearing from controllers' screens three months before the device was first tested, it suggests the device is not the cause of this issue. This provides an alternate explanation for the disappearance, thereby weakening the conclusion.
Skill tested: Weaken · how this choice captures the argument's function is the move to repeat next time.
92% picked this
The sudden disappearance of key
No Impact
This choice specifies where the problem occurs but doesn't impact the causal connection being made between the device and the disappearance of key information.
1% picked this

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