How did rule by a few or a small group work in the city states of italy

Below are the choices that can be found elsewhere:

Only monarchies ruled the city-states.
Republics allowed representatives elected by the population to rule.
Oligarchies governed through councils and elected officials.
Within each city-state, all men gathered to form a quorum that created laws and governed.

And the answer is "Oligarchies governed through councils and elected officials."

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