Necessary AssumptionDiff: Medium
Logic Breakdown
Passage Summary: A spokesperson claims their campaign worked because there is less litter on the streets now than there was before they started.
Conclusion: The 'Clean City' campaign has been a highly successful initiative.
Reasoning: The amount of trash currently found on the city's streets is much lower than the amount present when the campaign first started.
Analysis: The argument commits a classic causal fallacy by assuming that because the trash decreased *after* the campaign started, the campaign must have *caused* the decrease. For this conclusion to hold, the spokesperson must assume that no other factor is responsible for the cleaner streets. Look for a 'Necessary' assumption that rules out alternative causes or confirms that the campaign was at least partially responsible for the change. If you negate the correct answer—saying the campaign had nothing to do with the trash reduction—the argument falls apart.
Conclusion: The 'Clean City' campaign has been a highly successful initiative.
Reasoning: The amount of trash currently found on the city's streets is much lower than the amount present when the campaign first started.
Analysis: The argument commits a classic causal fallacy by assuming that because the trash decreased *after* the campaign started, the campaign must have *caused* the decrease. For this conclusion to hold, the spokesperson must assume that no other factor is responsible for the cleaner streets. Look for a 'Necessary' assumption that rules out alternative causes or confirms that the campaign was at least partially responsible for the change. If you negate the correct answer—saying the campaign had nothing to do with the trash reduction—the argument falls apart.
Passage Stimulus
Passage Redacted
Unlock Full Passage2.Which one of the following is an assumption required by the spokesperson's argument?
Correct Answer
A
It blocks the major alternative explanation: that the decline was already occurring at the same or faster rate before the campaign. Negation test: If trash was already declining at the same or faster rate prior to the campaign, the campaign wouldn’t be shown to be a rousing success just from the observed decline; the argument fails. So A is necessary.
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