In U.S. politics, what does the term "bipartisan" refer to?

The term "bipartisan" specifically refers to support or cooperation that involves both of the major political parties in the United States, which are the Democratic Party and the Republican Party. When legislation or policies are described as bipartisan, it indicates that members from both parties have agreed on a common position or have collaborated to achieve a particular goal. This collaboration is often essential for passing laws in a divided government where different parties control different branches or houses.

In contrast, the other choices reflect different concepts in politics. The presence of multiple political parties does describe a pluralistic political system but does not specifically convey the idea of cooperation between two major parties. Support from third-party candidates is more about the influence of smaller parties that operate outside the two-party system and does not relate to bipartisanship directly. A system that allows for no party affiliation refers to an independent stance, where individuals do not align themselves with any political party, which is also unrelated to the idea of bipartisan support.