Who made the greatest contribution to Hip Hop? Discuss the three major founders

Who made the greatest contribution to Hip Hop? Discuss the three major founders and innovators of Hip Hop, Kool Herc, Africa Bambaataa, and Grandmaster Flash. What are each of their innovations? How do their innovations differ and even build upon each other? What are elements that they have in common? In your opinion, how do their individual philosophies/ideologies, ethnic background, and regional positions inform their contribution to the art form? Please be thorough with your response.