The correct answer is A. They try to get their members elected whom they expect to vote along the party platform on issues.
Political Parties have their political platform - Democrats defend social and economic equality, the welfare state, support of labor unions, social programs and others. Republicans defend free market capitalism, strong national defense, deregulation, restriction on labor unions and others - and the way they can influence which platform is transformed into public polity is electing members that can vote in favor of them or not.
I think the most suitable options are (1)closing of the western frontier or <span>(2)industrialization in the North and the Midwest. I think, I'd go with second one.</span>
<span>The early modern era spans from 1945 to the present.
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