Final answer:
A theme is a central idea or message in a work of literature, and option B: 'People pay a high price for being overly ambitious' is an example of a theme.
Step-by-step explanation:
A theme is a central idea or message that is explored throughout a work of literature. In the context of the given question, option B: 'People pay a high price for being overly ambitious' is most clearly an example of a theme. This statement conveys a recurring idea in literature that excessive ambition can have negative consequences. It is a theme that is explored in many works, including F. Scott Fitzgerald's 'The Great Gatsby'.
Learn more about Themes in literature