Synonym of FAKE is IMITATION.

Explanation:
- Synonyms are words that have a similar meaning or can be used interchangeably in certain contexts.
- In the given options, the word that most closely matches the meaning of "fake" is "imitation".
- The word "fake" refers to something that is not genuine or authentic, but rather a copy or reproduction of something else.
- Similarly, the word "imitation" also refers to something that is not original but is made to resemble or replicate another thing.
- Both words imply a lack of authenticity or originality, suggesting that something is not what it claims to be.
- However, it's important to note that not all synonyms are perfect substitutes in every context. The word "fake" can have a broader range of meanings, including deception or fraud, whereas "imitation" primarily refers to a copy or reproduction.
- In this case, "imitation" is the closest synonym to "fake" among the given options because it captures the idea of something being a replica or a counterfeit version of the original.

Therefore, the correct synonym for FAKE is IMITATION.