Scientists studying a remote lake have observed unusual algae blooms occurring every few years. Local residents have attributed these blooms...
GMAT Information and Ideas : (Ideas) Questions
Scientists studying a remote lake have observed unusual algae blooms occurring every few years. Local residents have attributed these blooms to a nearby factory, citing the correlation between factory operations and bloom timing. Environmental scientist Dr. Rachel Martinez has discovered that the blooms coincide with natural climate cycles that occur on the same schedule. This finding indicates that the factory's role in causing the algae blooms ______
Which choice most logically completes the text?
has been definitively established by the timing correlation.
becomes more likely given the additional climate data.
is less certain than residents initially believed.
can be completely ruled out based on the climate evidence.
Step 1: Decode and Map the Passage
Create Passage Analysis Table
| Text from Passage | Analysis |
|---|---|
| "Scientists studying a remote lake have observed unusual algae blooms occurring every few years." |
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| "Local residents have attributed these blooms to a nearby factory, citing the correlation between factory operations and bloom timing." |
|
| "Environmental scientist Dr. Rachel Martinez has discovered that the blooms coincide with natural climate cycles that occur on the same schedule." |
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| "This finding indicates that the factory's role in causing the algae blooms ______" |
|
Provide Passage Architecture & Core Elements
Main Point: New scientific evidence reveals that algae blooms coincide with natural climate cycles, which provides an alternative explanation to residents' factory theory.
Argument Flow: The passage moves from establishing the phenomenon to presenting the residents' factory-based explanation, then introduces competing scientific evidence, leading to a question about implications.
Step 2: Interpret the Question Precisely
This is a fill-in-the-blank question asking us to choose the best logical connector. The answer must create the right relationship between what comes before and after the blank.
Step 3: Prethink the Answer
- The key situation: residents believed the factory caused the blooms because of timing correlation. But Dr. Martinez found that the blooms match natural climate cycles on the same schedule. This creates an alternative explanation for the timing pattern that residents used to support their factory theory.
- When we have two possible explanations for the same evidence, the original explanation becomes less certain. The climate cycles don't prove the factory isn't involved, but they show that the timing correlation could be explained by natural causes.
- So the right answer should indicate that the factory's role is less certain than it appeared when timing correlation was the only evidence considered.
has been definitively established by the timing correlation.
✗ Incorrect
- Claims the timing correlation "definitively established" the factory's role. This contradicts the passage logic - the new climate data actually undermines the certainty that timing correlation provided.
becomes more likely given the additional climate data.
✗ Incorrect
- Suggests the factory explanation becomes "more likely" with the climate data. The climate data provides an alternative explanation, which would make the factory explanation less likely, not more.
is less certain than residents initially believed.
✓ Correct
- States the factory's role is "less certain than residents initially believed." This perfectly captures the logical impact: residents had one explanation based on timing, but the climate cycle discovery provides an alternative explanation for the same timing pattern.
can be completely ruled out based on the climate evidence.
✗ Incorrect
- Claims the factory role "can be completely ruled out." Too extreme - the climate evidence shows an alternative explanation but doesn't definitively eliminate the possibility of factory involvement.