Answer:
The good answer is :
C. Relations between Islamic and Christian cultures were damaged immensely.
Explanation:
The Crusades were the result of deep emnity between two civilizations: Islamic and Christian. They were archrivals for domination of the known world until 1492, and controlling Jerusalem was a mutual goal; their actions had religious basis and justification, but the consequences were also political, economic and commercial. Each side looked at the other as impious and blasphemus, and thought it had the exclusive right to dominate the Holy City and the Holy Land. The Crusades are a very dark chapter of a deadly historic rivalry of two mutually excluding camps. They remain in history and in the collective memory of many societies. Even today, Muslim terrorists  refer to the times of Crusades and  see themselves as involved in a new crusade against "infidels" who humilliate Muslims and desecrate Muslim lands.