Which factor was an important contributor to the start of world war 1

Option: D. European Countries were competing with one another for control  in Africa and Asia.

Explanation:

Before World War I, the European nations were expanding their territories in Africa and Asia by increasing power and wealth. These European countries were competing for imperialism with their neighboring because of the raw material they were getting out of it and the tension was growing in these created empires by Europeans in foreign counties. The growing conflict and passion for larger empires led to an increase in dispute that helped start the world into World War I.    

d.prevent the spread of communism outside of eastern europe.

the answer to number 5 is fort sumter