One of the limiting factors in human physical performance is the amount of oxygen that is absorbed by the muscles...
GMAT Critical Reasoning : (CR) Questions
One of the limiting factors in human physical performance is the amount of oxygen that is absorbed by the muscles from the bloodstream. Accordingly, entrepreneurs have begun selling at gymnasiums and health clubs bottles of drinking water, labeled "SuperOXY," that has extra oxygen dissolved in the water. Such water would be useless in improving physical performance, however, since the only way to get oxygen into the bloodstream so that it can be absorbed by the muscles is through the lungs.
Which of the following, if true, would serve the same function in the argument as the statement in boldface?
Understanding the Passage
| Text from Passage | Analysis |
| "One of the limiting factors in human physical performance is the amount of oxygen that is absorbed by the muscles from the bloodstream." |
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| "Accordingly, entrepreneurs have begun selling at gymnasiums and health clubs bottles of drinking water, labeled 'SuperOXY,' that has extra oxygen dissolved in the water." |
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| "Such water would be useless in improving physical performance, however," |
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| (Boldface 1) "since the only way to get oxygen into the bloodstream so that it can be absorbed by the muscles is through the lungs" |
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Overall Structure
The author presents a scientific fact about oxygen limitation, describes a market response to this limitation, then refutes the effectiveness of that response using biological reasoning. The logic flows: problem identification → proposed solution → rejection of solution with supporting evidence.
Main Conclusion: SuperOXY water would be useless in improving physical performance.
Boldface Segments
- Boldface 1: the only way to get oxygen into the bloodstream so that it can be absorbed by the muscles is through the lungs
Boldface Understanding
Boldface 1:
- Function: This serves as the scientific evidence/reasoning that explains why the author's conclusion is correct
- Direction: Supports the author's conclusion (same direction) - it provides the biological basis for rejecting the effectiveness of oxygenated water
Structural Classification
Boldface 1:
- Structural Role: Supporting evidence/premise that justifies the main conclusion
- Predicted Answer Patterns: "evidence supporting the conclusion," "reason for the author's position," "premise that supports the main claim"
This statement about replacing water lost during exercise with ordinary tap water doesn't serve the same function as the boldface. The boldface explains WHY SuperOXY water can't work (oxygen pathway limitation), while this choice just mentions hydration replacement without addressing the oxygen delivery mechanism that's central to the argument.
✓ CORRECT - This serves the same function as the boldface statement. Both provide scientific reasoning for why SuperOXY water would be useless. The boldface argues that oxygen can't reach muscles through drinking (pathway problem), while this choice argues that muscles already get more oxygen than they can use (absorption problem). Both explain why adding oxygen to drinking water won't improve performance.
This statement about world-class athletes performing well without SuperOXY water provides empirical evidence rather than scientific reasoning. The boldface explains the biological mechanism of why the water can't work, while this choice just shows that people succeed without it. These serve different argumentative functions.
This talks about exercise increasing oxygen uptake ability, which is about improving the body's capacity rather than explaining why SuperOXY water specifically doesn't work. The boldface provides a reason against the water's effectiveness, while this discusses exercise benefits - different functions entirely.
This broadens the discussion to other limiting factors beyond oxygen, which shifts focus away from the oxygen-specific argument. The boldface specifically explains why oxygen can't be delivered through drinking water, while this choice minimizes oxygen's importance altogether - opposite functions.