The correct answer is 'a short story'. A narrative is a work in which the narrator tells a story about something that happened in their lives, which is often the format for short stores. Persuasive essays are about using rhetoric to change an audience's views on a topic, and, while anecdotes can be used as a rhetorical strategy, are less likely to contain a narrative than a short story. Expository and informative essays are essentially the same (although there are some differences), as they both provide factual information on a topic rather than telling a story, so narratives are rare in this form of writing.
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