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Find the choice that makes the argument's conclusion less likely to be true.
Answers that look negative but attack a claim the argument never relied on.
Find the assumption the argument depends on, then pick the choice that undermines it.
Which one of the following, if true, would most undermine the geologist's explanation of why Earth's rate of rotation increased over the last decade?
In the beginning of the
Opposite (if anything): more correlation strenthens, if anything
2% picked this
During the past decade, other
Why this is right
Disrupts the assumption that the tectonic plate movement causes a net decrease in the Earth's radius by raising the possiblitiy that any decreases are counteracted by other movements.
Skill tested: Weaken · how this choice captures the argument's function is the move to repeat next time.
89% picked this
Only skillful figure skaters succeed
Limiting the example to a subset of skaters doesn't change the law of physics the example is exemplifying.
1% picked this
Since the time of the
This might seem at first like an alternative explanation for the current rate of rotation increase. It isn't, however, because the reason for the historic fluctuations aren't specified. We can't, therefore, say the current change in rotation rate is any less likely to be due to the contraction of Earth's radius that it was before we knew that similar rotation fluctuations have happened throughout history.
5% picked this
Increased volcanic activity over the
The overall amount of tectonic movement increasing in the last decade doesn't attack the idea that the movement ultimately leads to a net decrease in the size of the Earth.
2% picked this
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