Choose the word that is most nearly the opposite in meaning of the word given in capitals.
ILLEGIBLE
A. Concise
B. Imitable
C. Clean
D. Readable

Hint: Illegible means not legible, something which is not clear or blurry that cannot be read, usually because of poor handwriting or faded print.
Example: This boy's handwriting is almost illegible.
Example: The letter was illegible.
Words similar to illegible are scribbled, faint, cramped, indistinct, etc.

Complete step by step answer:
To choose the word which gives nearly the opposite meaning of the given word, let us analyse each option individually.

Concise: giving information about a topic, clearly but briefly, putting in much information with the help of a few words. Example: This data is very concise with information that is important.
Example: The documentary was concise, therefore interesting.
Imitable: an activity which can be worthy of being copied, capable of being imitated.
Example: His character in the story is easily imitable.
Example: She has many imitable traits.
Clean: to be not dirty, that is free of stains or marks, morally innocent, uncontaminated.
Example: The roads are clean nowadays.
Example: He came out clean of the investigation.
Readable: something which is capable of being processed, that is, able to read. Example: The posters at the sidewalk are readable.
Example: The application was not readable.

So, the correct answer is “Option D”.

Note:
Do not confuse the correct answer with the word ‘clean’ as clean doesn’t necessarily mean readable. Readable is also used in place of understandable or comprehensible. Some words opposite to illegible are legible, clear, tidy, lucid, distinct, etc. Some words synonymous to illegible are messy, unreadable, scribbled.