Why did the Roman Empire collapse? Please write an entire essay --> (intro - 1 body paragraph - conclusion)

In desperate need of soldiers to help with the invasions, Rome hired mercenaries to defend its borders. According to some historians, many were Germanic warriors who did not feel loyalty to Rome. ... The most evident factor of the Roman Empire's fall was the invasions.

Explanation:

d. i assume the underlined word is "role." reformat if it isn't.

explanation:

role is closest to part because when replacing words, "playing a vital decision," "playing a vital activity," and "playing a vital dollar" don't make logical sense. the only meaningful choice is "playing a vital part."

this fits one of merriam-webster's definitions of role: "a function or part performed especially in a particular operation or process."

answer; ratification;