The correct answer is B. Establishment of crusader states.
Explanation
The first crusade is the name of a political, social, and mainly religious phenomenon that was characterized by starting a military campaign, armed pilgrimage, and settlement of Christian kingdoms in a territory in dispute with the Muslim community from the 11th to 13th centuries. As a result of these confrontations, the Crusader States were created, feudal political entities of European origin located in the territories of eastern Europe that had been taken from the Muslims. These territories were of great importance to the Christian church because it was the Holy Land there and many of the events in the Bible occurred in that region. So the correct answer is B. Establishment of crusader states.