One-word substitution (vocabulary): Choose the correct term for “that which cannot be corrected.” Select the single best word that matches the definition exactly.

Given data

• Target meaning: impossible to correct, reform, or improve (esp. habit/behavior).

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