Which common language unify the islamic empire both politically and economically

Arabic

Explanation:

Arabic is the common language that helped unify the Islamic Empire both politically and economically. Although Arabic originated between the 1st and 4th century CE, it was standardized around the 8th century. By this time, Classical Arabic was an essential prerequisite for rising into the higher classes throughout the Islamic world. This led to most educated people learning Arabic and using it as an official language across the Islamic world, helping unify these diverse territories.

the answer is b. osage.

detente translated to english means politics