Respuesta :
I think the correct answer would be the first option. The terms plausible and believable are synonyms. Plausible means something that is probable, acceptable, it is likely true. Believable would mean the same as well, it is something that is realistic, credible or acceptable. Words or phrases that means the same are synonyms.
The way and manner the terms are related are they show similarity and opposites.
What are Synonyms?
This refers to the words that have a similar meaning to another word and can be used interchangeably.
Hence, we can see that based on the given word: "plausible", we can infer that the synonym means something that can be believed, while the antonym means the opposite and is something unbelievable.
Read more about antonyms and synonyms here:
https://brainly.com/question/21370606
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