Explanation:

- The word "fertile" is an adjective often used to describe land that is able to produce abundant vegetation or crops.

- Option 1: Barren

- This is the correct antonym for "fertile."

- Barren describes land that is too poor to produce much or any vegetation.

- Option 2: Civilized

- This word is unrelated to the concept of fertility.

- It's an adjective referring to a society that is advanced in cultural, social, and political aspects.

- Option 3: Sane

- This pertains to mental health and soundness of mind.

- It doesn't relate to fertility or describe land.

- Option 4: Tough

- This is about the texture or difficulty, not fertility.

- It doesn't serve as an antonym for fertile land.

The correct answer is Option 1: Barren.

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