Answer:
I think it's C. not gonna say it is but I think that's right. hope this helps
The crusades were considered a turning point in history because the pope urban 2 wanted the christians to fight the muslims so that they could have back the control over the holy lands
Centralized government authority, became ruler of Austria in 1740 after a pragmatic sanction was issued to allow this person to rule. Examined natural laws governing the universe
All of these could be a possible answer but i think the second choice was the most prevalent conflict at that time.