Difficulty: Medium
Correct Answer: Only Conclusion II follows
Explanation:
Introduction / Context:
The premises relate three sets: flies, ants, and insects. One is a particular inclusion; the other is a universal inclusion. We must judge two proposed conclusions.
Given Data / Assumptions:
Concept / Approach:
From a “some” statement we cannot jump to “all.” However, if all insects are ants, then (assuming insects exist) there certainly exist ants that are insects — giving a “some” conclusion about ants and insects.
Step-by-Step Solution:
1) C1 (“All flies are ants”) is not forced: the premise only states that some flies are ants; other flies could be non-ants.2) C2 (“Some ants are insects”) is necessary if insects exist, because every insect is an ant; therefore the insect population (non-empty in typical reasoning sets) sits inside ants, witnessing “some.”
Verification / Alternative check:
Model with a Flies set that partly overlaps Ants and partly lies outside; make Insects a subset within Ants. Premises hold while C1 fails and C2 holds.
Why Other Options Are Wrong:
Options claiming C1 or both C1 and C2 are too strong; “neither” ignores the guaranteed existence of insect-ants in standard settings.
Common Pitfalls:
Illicit conversion from “some” to “all,” and overlooking the existential import typically assumed for familiar categories such as insects.
Final Answer:
Only Conclusion II follows.
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