The Crusades were military expeditions undertaken by a. european christians who wanted to destroy constantinople
b. muslim armies who sought to conquer Europe
c. European Christians to regain the Holy Land from the Muslims
d. Christian and Muslim armies who joined to fight the Mongols

European Christians to regain the Holy Land from the Muslims

Explanation:

The "crusades" were, indeed, military expeditions managed by the European Christians. Its main purpose was to recover the "Holy Land," the area situated between the Mediterranean Sea and the Jordan River. It was under the Islamic rule that was brought about by Muslim expansion.

Many participants volunteered because this was also viewed as a way of removing one's sin and renewing spiritual relationship with God.

answer: what was the us involvement in ww1? although the u.s. tried to remain neutral when ww1 broke out, it finally joined on april 6, 1917 after declaring war on germany. the reason for america to become involved in ww1 was germany's unrestricted submarine warfare, which had already sunk several american merchant ships.

explanation:

"a shortage of traditional labor created new opportunities in the workplace. a major cause of the internment of japanese americans during world war ii was. racial prejudice. in the early 1940's, the "destroyers-for-military-bases deal" with great britain and the lend-lease act were evidence that the united states."