Which of These Historical Forces Helped Give Rise to a Climate

Which of these historical forces helped give rise to a climate conducive to terrorism?

A) Direct military confrontations became more dangerous in the nuclear age.
B) The rise of the Cold War created a global climate of hostility.
C) European colonialism continued to expand unchecked.
D) A global gag order on covering massive, political violence in the media.
E) The rampant growth of capitalism.