Explanation:

- "Adept" means being highly skilled or proficient in a particular area.

- Option 1: expert

- "Expert" means someone who has comprehensive and authoritative knowledge or skill in a particular area.

- Option 2: proficient

- "Proficient" means competent or skilled in doing or using something.

- Option 3: deft

- "Deft" means demonstrating skill and cleverness.

- Option 4: inept

- "Inept" means having or showing no skill; clumsy.

Given the definitions, the antonym for "adept" is "inept" since they have opposite meanings.

Option 4: inept is the correct antonym.

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