The correct answer is C. The central idea of the text
Explanation:
In each text, there is a central idea or thought, and the purpose of the author is to develop this idea. This is possible when the author adds relevant details such as sub-ideas, evidence, examples, etc. related to this central idea. For example, in a text about the history of technology, the author will need to add details about relevant technological advances in different historical periods. This implies the important and relevant details are used to explain, support and develop the central idea of the text, rather than to support your opinion or the author's point of view.
If you are going to write a short story, you don't need to make things up entirely. You should always use as much creativity as you can, but you can also take elements from real life and incorporate it in your story.