State governments are primarily required to allow citizens to choose their representatives, which ensures democratic participation. While some of the other options are common practices, they are not mandates. Creating bicameral legislatures and collecting sales taxes are determined by states individually. ;
State governments are required to allow citizens to choose representatives, reinforcing democratic values. While options like creating two legislative houses and collecting sales taxes are common, they are not mandates for all states. Thus, the correct answer is option C.
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