Your answer is C categories because categories help organize any type of writing such as essays, speech's, and documents also its not A because a theme is like the main idea of the speech like the whole point of it what do you want the people to know and learn its also not B because details is what the the speech is made up of or statements to support your speech why do you agree with this and disagree with that and when it came down to rather C, or D I choose C because D thesis statements are use as a preview what the speech will be about what do the spectators look toward to also known as the grabber in the speech.
Your answer is C.