Sufficient AssumptionDiff: Medium
Logic Breakdown
Passage Summary: We haven't found methane on Planet 253. Because microbes always make methane, we know there are no microbes there. Therefore, the planet is completely lifeless.
Conclusion: There is definitely no life on Planet 253.
Reasoning: There is no methane on Planet 253, and since microbes always produce methane, there are no microbes on the planet.
Analysis: The argument successfully proves the absence of microbes, but it takes a massive leap to conclude there is no life *at all*. To make this conclusion follow logically, we need a 'Sufficient Assumption' that bridges the gap between 'no microbes' and 'no life.' The argument needs a rule stating that all life on this planet must be microbial, or that life cannot exist without the presence of microbes. Look for an answer that establishes that if there is life, there must be microbes (the contrapositive of which is: no microbes means no life).
Conclusion: There is definitely no life on Planet 253.
Reasoning: There is no methane on Planet 253, and since microbes always produce methane, there are no microbes on the planet.
Analysis: The argument successfully proves the absence of microbes, but it takes a massive leap to conclude there is no life *at all*. To make this conclusion follow logically, we need a 'Sufficient Assumption' that bridges the gap between 'no microbes' and 'no life.' The argument needs a rule stating that all life on this planet must be microbial, or that life cannot exist without the presence of microbes. Look for an answer that establishes that if there is life, there must be microbes (the contrapositive of which is: no microbes means no life).
Passage Stimulus
Passage Redacted
Unlock Full Passage26.The conclusion drawn above follows logically if which one of the following is assumed?
Correct Answer
D
Assuming that absence of microbes implies absence of life (No microbes -> No life) completes the chain with the given No methane -> No microbes, yielding No methane -> No life, which is exactly the conclusion.
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