One-word substitution (vocabulary): That which cannot be read Select the single best word that matches the description.

Given data

• Definition: impossible or very hard to read (e.g., handwriting).

Reasoning through options Illegible — not readable. Correct. Ineligible — not qualified; unrelated. Negligible — so small as to be not worth considering. Incorrigible — cannot be corrected; unrelated to reading.