Answer:
The statement that most clearly describes why an author creates a particular mood in a story is to help readers understand the context
Step-by-step explanation:
As many of the motivations for the characters and the way the setting works according to any specific period or society influence the context of a story it is a very functional tool for author to set the mood of the story, it will not always be the same this will be changing according to the development of both the story and the characters and that's why it helps readers not only to connect with the story but to get it better.