Why Were the Political Forms of the Greek City-States and the Greek

Why were the political forms of the Greek city-states and the Greek concept of citizenship so unprecedented and unique?

A) They allowed all the inhabitants of a city-state, irrespective of race or gender, to vote equally.
B) They represented a radical departure from long-held communal values, as the rights of the individual henceforth took precedence.
C) They affirmed the right of all Greek inhabitants to an equal share in the state's governance.
D) They were based on the concept of citizenship for all free inhabitants and allowed for some degree of shared governing, except in tyrannies.