What are facts, examples, or descriptions that help explain or prove the main idea?

Supporting details are pieces of information that provide evidence or clarification for the main idea of a text. These can include facts, examples, or descriptions that enhance the reader's understanding and illustrate the main point being communicated. By including supporting details, writers can strengthen their arguments and help readers grasp the message more effectively. This is essential in both informational and narrative texts, as it allows for a deeper comprehension of the topics or themes presented. The other options do not fit this definition; conclusions summarize the findings, themes represent overarching messages, and protagonists are the central characters in a story.