An anecdote is a brief story about a certain person or an event. Anecdotes are usually created interesting and humorous that aims in making people have fun while relating it to a specific subject matter that the listeners can learn or acquire more ideas.
I believe the correct answer is B. end on a note that's likely to stick in the reader's mind.
If you want your essay to stick out from a bunch of other similar essays, you need to have a good 'punchline.' There has to be something in your conclusion which will make your readers remember the essay if you want to differ from a sea of other writers.