I think it would be number 4
I believe the answer is C because it tells you that the story is important and that it is incredible only once each and does not over embellish.
Answer:
A modifier changes, clarifies, qualifies, or limits a particular word in a sentence in order to add emphasis, explanation, or detail. Modifiers tend to be descriptive words, such as adjectives and adverbs. ... The additional details in the sentence, by way of modifiers, engage the reader and hold their attention.
Explanation:
All convincing speakers must perfect the art of persuasion.
Someone who has perfected the art of persuasion would be highly skilled at convincing people of different things.