Your answer is c, the supreme court ruled that unions did not have...
Factor 1: Who decides to run for office and what advantages candidates have over one another.
Factor 2: Incumbency. Usually the incumbent (the person already serving in the office) has a large advantage over challengers, unless negative events have the voters wanting to get rid of incumbents.
Factor 3: The way congressional districts are drawn. There have been court cases recently about "gerrymandering" -- attempts by a party in power to draw district boundaries in ways that will serve to perpetuate that party's power.
It crease to exist because he was meant to be born in this world.