Ais a form of government in which the leader is not a monarch and certain citizens have the right to vote.
a. polis
c. dictatorship
b. republic
d. circus maximus

 b. republic

Further detail:

A republic differs from a democracy in that when a government is fully a democracy, that means voting and participation in government by all citizens.  A republic may limit voting and political rights to certain types of citizens.  Many republics in history, for instance, have limited voting rights to those who owned a certain amount of property.  Britain was like that for a long time, and the United States started out that way as well.

We think of the United States today as a democratic republic, because voting rights are granted to all citizens age 18 or older, but voters elect representatives who serve in the government of the republic on their behalf.

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