Difficulty: Easy
Correct Answer: 97
Explanation:
Introduction / Context:Number classification often contrasts primes with composites (including perfect squares). Spotting the sole prime quickly identifies the outlier.
Given Data / Assumptions:
Concept / Approach:Classify each as prime vs composite. A perfect square automatically belongs to the composite class (except 1, which is neither prime nor composite).
Step-by-Step Solution:Test 88 → composite.Test 132 → composite.Test 121 → 11^2 → composite.Test 97 → no small prime factors; prime.
Verification / Alternative check:Divisibility checks confirm 97 is not divisible by primes ≤ 9 (2,3,5,7), so it is prime.
Why Other Options Are Wrong:88/132/121: All are composite (121 is square of 11).
Common Pitfalls:Mistaking 121 as prime due to identical digits; it is 11 * 11.
Final Answer:97
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