Difficulty: Easy
Correct Answer: Incorrigible
Explanation:
Given data
Reasoning through options
Incorrigible — not able to be corrected, improved, or reformed; the exact match. Unintelligible — cannot be understood; not about correction. Indelible — cannot be removed/erased (e.g., ink, memory); not about correction of a person/thing. Illegible — cannot be read (poor handwriting); unrelated to correction.
Final Answer
Incorrigible
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