Final answer:
The division of the United States into opposing camps has been influenced by the polarization due to changes in party allegiance, the influence of distinct political cultures within states, and the impact of the Electoral College. The correct option is b.
Step-by-step explanation:
According to the research of psychologists Conor Seyle and Matthew Newman, the division of the United States into opposing camps over the last 10 years has been a complex phenomenon with various contributing factors.
A primary factor for this division is a polarization characterized by a party-in-government phenomenon driven by a decades-long sorting of the voting public, or a change in party allegiance in response to shifts in party position.
This sorting thesis suggests that before the 1950s, voters were mainly concerned with state-level party positions but over time, there has been a shift toward national-level issues.
Furthermore, theorists like Daniel Elazar have suggested that differing political cultures within states—moralistic, individualistic, and traditionalistic—stem from the migratory patterns of early settlers, thus shaping attitudes and beliefs about government functions and expectations.
Additionally, economic fortunes, regional political cultures and the existence of the Electoral College have all played a role in enhancing this division.
However, the concept of 'red states versus blue states' is often an oversimplification, as most states have a mix of Republicans and Democrats, suggesting a more nuanced 'purple states vs. violet states' political landscape. The correct option is b.