Which of the following best describes writing that shares an incident that made an impact in the writer’s life?
a. reflective essay
b. memoir
c. personal narrative
d. eyewitness account

The answer is indeed letter A. reflective essay.

A reflective essay is one in which the author not only tells readers about his/her experiences, but also analyzes how those experiences changed his/her life, what sort of reverberations they have brought to his/her growth as a person.

A memoir is similar to a biography or an autobiography, but with an outward focus - what the person has witnessed instead of his/her own life per se. It's usually much longer than a reflective essay.

A personal narrative also tells readers about an incident that took place in the writer's life. It differs from the reflective essay in the sense that the essay also analyzes the events' effects, while the narrative focuses more on telling the story.

An eyewitness account is merely a description someone gives of an event they have seen, even if it's not related to their own lives at all - for instance, witnessing a robbery from a distance.