Answer:
Correct answer is B. hostility between Christians and Muslims
Explanation:
A is not correct as this was actually a good effect of those wars, as the Silk Road was flourishing in that period.
B is the correct answer as those wars started a period of religious turbulences between two religion, that exist even today.
C is not correct as feudalism disappeared in the meanwhile.
D is not correct as the role of the Pope was not as stronger as it was before the Crusades and after them. They lost a lot of authority.
