TRUE. <span>Gregorian chants developed because Pope Gregory I wanted to standardize masses.
Gregorian chant is a plainchant only used for Catholic church liturgy. Charlemagne made it the official Catholic liturgical chant in compliance to Pope Gregory I dictate.
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Answer: His lynching two years later, in response to the commutation of his death sentence, became the focus of social, regional, political, and racial concerns, particularly regarding antisemitism. (wikipedia)
Explanation:
Rome declined due to a series of invasions from outside nations and corrupt government officials.
"<span>c. Persia maintained strong armies" would be the best option from the list, since for much of history Persia was a dominating military force in the Middle East. </span>