Read the following statements and determine which inference(s) logically…

2026

Read the following statements and determine which inference(s) logically follow.

Statements:
All scientists are researchers.
Some researchers are smart.

Inference I: All scientists are smart.

Inference II: Some scientists are smart.

Inference III: Some smart people are researchers.

Inference IV: Some researchers are scientists.

  1. A.

    Only III and IV follow.

  2. B.

    Only inference III follows.

  3. C.

    Both inferences IV and II follow.

  4. D.

    All follow

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Correct answer: A

Premises:
All scientists are researchers.
Some researchers are smart.

Inference I — All scientists are smart: Does not follow. The fact that some researchers are smart does not mean every scientist is smart.

Inference II — Some scientists are smart: Does not follow. The smart researchers need not be scientists.

Inference III — Some smart people are researchers: Follows. “Some researchers are smart” can be converted to “Some smart people are researchers.”

Inference IV — Some researchers are scientists: Follows under the standard aptitude-syllogism/Venn-diagram convention. If all scientists are researchers, then scientists are contained within researchers, so some researchers are scientists.

Therefore, only inferences III and IV follow. Hence, Option A is correct.

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