The Most Devastating Consequence of the Crusades Was

The most devastating consequence of the Crusades was:

A) the new religious and political ethos that informed the reconquest of Iberia.
B) the development of Islamic and Christian doctrines of holy war.
C) the underlying justification of the English wars against the Welsh and Scots.
D) the justification for the massacre and dispossession of the "heretics" of southern France.
E) all of these