What does the term "Solid South" refer to?

The term "Solid South" refers to a one-party political system in the Southern United States, primarily characterized by the dominance of the Democratic Party in the years following the Civil War and continuing well into the late 20th century. This phenomenon arose in response to the Reconstruction era and the subsequent disenfranchisement of African American voters, leading to a political landscape where the Democratic Party became the unchallenged choice of white voters in the South. As a result, electoral outcomes in the region were consistently predictable, with a strong alignment of voters against the Republican Party, which had been associated with the Union and changes resulting from the Civil War.

The other choices do not accurately capture the essence of the "Solid South." A multi-party political system implies a diversity of parties actively competing for power, which was not the case in the South during the height of the Solid South era. Similarly, a coalition of urban voters would suggest an alignment based on urban demographics and interests, which contrasts with the predominantly rural and conservative political landscape of the Southern states at that time. Bipartisan cooperation suggests a collaborative effort between different political parties, which did not characterize the Solid South, as the Democratic Party maintained a tight grip on political power and there was minimal cooperation with or influence