the authors purpose is to inform readers, so therefore it needs to be understandable and clear how to do what the reader went to the source to learn how to do, so, A would be the answer.
A. How to make the content understandable for readers
The purpose of an informative text is not to entertain so option B is incorrect. Option C is also incorrect because the informative text is not meant to advertise or be pretty. It's goal is to inform. Therefore, the content needs to be clear and understandable. This is the exact opposite of option D. Content that the reader has to solve or navigate is not informative or clear. It's important when structuring a text to identify the text's purpose. All texts should draw the reader in, but using the text's structure is not the best way to do that.
words that characterize a character's personality or characteristics that define them. To put it another way, how would you characterize that persona to a stranger