Answer:
a. Starting in the sky, the camera descends on the two actors sitting next to a campfire. A narrator in the background explains the circumstances that brought the two characters together.
Explanation:
An exposition is a background story told in the first section of a movie, book, or story to explain the foundation of the story. It gives the audience an idea of the plot, theme, and setting of the story to follow.
Option A satisfies the definition of an exposition, for, in the first sentence, we see a description that fits into the first section of a movie. It is then followed by narration or exposition by the writer who explains the circumstances that brought the two actors together. This explanation will give the film viewer an insight into the plot, theme, and setting of the story.