Answer:
A. Thesis statement
Step-by-step explanation:
A narrative essay is a type of essay that has a single theme. All incidents, happenings, and characters revolve around a single presented idea. It describes people, presents their conversation, and narrates their experiences to teach lessons to readers. For these reasons, there is a possibility to use vivid descriptions, picturing the main characters, situations, and etc. So, option B is also wrong.
Also, this is a form of writing where the author focuses on the lesson (experience) that he/she has learned from the past. To show everything in greater detail and prove the idea he/she can use different rhetorical devices: metaphors, similes, persuasive techniques, and etc. So option C is wrong.
A narrative essay has three main elements of a plot: character, theme, and dialogue. Definitely, it has a plot. Option D is wrong.
To sum up, vivid descriptions, rhetorical devices, and plot can characterize the narrative essay.
But a thesis statement is not an element of characterization. It is an element of the structure of an essay. As it is a statement that appears at the middle or end of the introductory paragraph. It summarizes the main point or claim of the essay (usually expressed in one sentence).