What Was the Most Important Reason That Drove European Powers

What was the most important reason that drove European powers in their rush to increase their imperialist holdings in Africa?

A) The quest for new markets prompted by rapid industrialization at home
B) The rivalries between European nations and fears that other countries would claim Africa first
C) The strong desire to extend Christianity throughout Africa
D) The goal to bring European technological advantages to Africans
E) The fear of Russian economic expansion into Central Africa and world domination