Identify The ConclusionDiff: Medium
Logic Breakdown
Passage Summary: A scientist claims that ice ages happened because there were so many plants on Earth that they sucked all the heat-trapping carbon dioxide out of the air, causing the planet to freeze.
Conclusion: The primary driver behind the occurrence of ice ages was the global proliferation of plant life.
Reasoning: Plants consume carbon dioxide, which is a heat-trapping gas; therefore, an abundance of plants leads to atmospheric cooling by depleting that gas.
Analysis: This is a classic 'Identify the Conclusion' task where the main point is stated right at the beginning. The rest of the stimulus provides a causal chain—plants eat CO2, CO2 holds heat, less CO2 means less heat—to explain why that first sentence is true. Even though the final sentence starts with 'Thus,' it is actually a sub-conclusion that explains the final step of the mechanism. The main conclusion is the overarching claim that vegetation growth was the ultimate cause of the ice ages.
Conclusion: The primary driver behind the occurrence of ice ages was the global proliferation of plant life.
Reasoning: Plants consume carbon dioxide, which is a heat-trapping gas; therefore, an abundance of plants leads to atmospheric cooling by depleting that gas.
Analysis: This is a classic 'Identify the Conclusion' task where the main point is stated right at the beginning. The rest of the stimulus provides a causal chain—plants eat CO2, CO2 holds heat, less CO2 means less heat—to explain why that first sentence is true. Even though the final sentence starts with 'Thus,' it is actually a sub-conclusion that explains the final step of the mechanism. The main conclusion is the overarching claim that vegetation growth was the ultimate cause of the ice ages.
Passage Stimulus
Passage Redacted
Unlock Full Passage13.Which one of the following most accurately expresses the main conclusion of the scientist's argument?
Correct Answer
E
E matches the scientist’s main point: that unusually rich worldwide vegetation was almost certainly the cause of the ice ages. Its strength (“almost certainly”) mirrors “little doubt,” and it states the precise causal claim the rest of the passage supports.
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