Hello!
The answer is: C. Rome was developing a new form of democracy.
Why?
Discarding the options:
A. Rome was enjoying peace and prosperity: False, Rome was enjoying a terrible violent period while the Social War was developing (91 to 88 B.C.)
B. Rome was enthralled in a civil war: False, Rome was fighting (and winning) against the Italians allies rebels because the Romans were not willing to give the same civil rights of Romans to the Italian allies.
C. Rome was developing a new form of democracy: True, after the Social War ended, the Roman Republic decided to extend the Roman citizenship to all communities of the peninsular Italia, giving the same rights to almost all Italian allies.
D. Rome was in a bitter war while fighting against Greece, Mesopotamia, and other invading forces: False, from 91 B.C. to 88 B.C.: False, the Rome Republic was in a war against the Italian allies.
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