How does the author's use of repetition help develop the central idea? A. It convinces the world leaders that America needs a radical change in the field of politics. B. It emphasizes the fact that Americans live in fear and that America is not a safe place anymore. C. It highlights the idea that America is facing a serious national problem, and all leaders should be responsible enough to do something about it. D. It reinforces the idea that Americans are on the edge of losing their patience, and it's time they exercised their right to think and speak freely.