What do you understand by "exposition"? a.) the part where the story moves to a very interesting point b.) the setting of the scene that includes introduction of characters c.) the part where the main conflict of the story is solved d.) the end of the story

The exposition means it is a literary device used to introduce background information about events, settings, characters etc. 

for an example  The exposition in star wars is the opening title sequence that gives information about the past events to the viewers. The crawling text on the screen at the beginning of each part gives the audience every piece of information they need to understand the upcoming events in the film. The opening lines usually begin like this: “A long time ago in a galaxy far away, far away…”

In the thesis statement in the beginning