One long-term effect of the Crusades on European philosophy and ideology was:

A) The Roman Catholic Church gained more power B) The decline of Feudalism and manor life C) Nobility gained more power D) States further decentralized

A) The Roman Catholic Church gained more power

The Crusades led to increased power and influence for the Roman Catholic Church in European society. The Church's role in promoting and leading the Crusades expanded its authority and influence over political, social, and religious matters. This resulted in the consolidation of power within the Church and shaped European philosophy and ideology for centuries to come.

Note: It's not A!

B) The decline of Feudalism and manor life

One long-term effect of the Crusades on European philosophy and ideology was the decline of feudalism and manor life. The Crusades disrupted the traditional feudal system by encouraging knights, nobles, and peasants to leave their lands and homes to participate in the holy wars. This led to a weakening of the feudal structure, as resources were drained and traditional obligations were neglected. The experiences and new ideas brought back by the Crusaders also played a role in shaping a more cosmopolitan and less isolated worldview, contributing to the decline of feudalism and the rise of new social and economic structures in Europe.