Necessary AssumptionDiff: Medium
Logic Breakdown
Passage Summary: Eating sugar makes kids produce a lot of adrenaline, which is why the author thinks sugar might be linked to making ADD symptoms worse.
Conclusion: Consuming sugar might worsen attention deficit disorder (ADD) in children.
Reasoning: A study showed that children produce high levels of adrenaline shortly after eating sugar, particularly when that sugar comes from candy.
Analysis: There is a significant logical gap here between the chemical premise (adrenaline) and the behavioral conclusion (ADD). The author is assuming that high levels of adrenaline actually contribute to or worsen the symptoms of ADD. If adrenaline had no effect on ADD, the fact that sugar causes adrenaline spikes would be irrelevant to the conclusion. To find the necessary assumption, look for the choice that links these two concepts together.
Conclusion: Consuming sugar might worsen attention deficit disorder (ADD) in children.
Reasoning: A study showed that children produce high levels of adrenaline shortly after eating sugar, particularly when that sugar comes from candy.
Analysis: There is a significant logical gap here between the chemical premise (adrenaline) and the behavioral conclusion (ADD). The author is assuming that high levels of adrenaline actually contribute to or worsen the symptoms of ADD. If adrenaline had no effect on ADD, the fact that sugar causes adrenaline spikes would be irrelevant to the conclusion. To find the necessary assumption, look for the choice that links these two concepts together.
Passage Stimulus
Passage Redacted
Unlock Full Passage20.Which one of the following is an assumption on which the argument in the magazine article depends?
Correct Answer
D
The argument depends on the link that increased adrenaline can worsen ADD. Negation test: if increased adrenaline could not make ADD more severe, then showing that sugar increases adrenaline would give no reason to think sugar exacerbates ADD; the conclusion would collapse. So D is necessary.
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