Correct Answer: Genuine

Solution : The correct option is the first option.

In the context of the word authentic, genuine is the most appropriate synonym because it closely aligns with the meaning of authentic, which means genuine, real, or true. It refers to something that is not a copy, imitation, or counterfeit. The other options are either antonyms or have different shades of meaning.

The meanings of the other options are as follows:

• False means not true or fake. For example, false information is incorrect or misleading.
• Doubtful means uncertain or questionable. When something is doubtful, it's not considered genuine or trustworthy. For instance, a doubtful claim is one that is not easily believed.
• Corrupt refers to something that has been altered or tainted in a way that makes it dishonest or morally compromised. For example, a corrupt document has been tampered with to deceive others.