[单项选择]The Democratic and Republican parties are the largest and most competitive organizations in the American community. Americans almost inevitably become Democrats or Republicans because there is usually no other place for them go to. Moreover, because the rivalry of these parties is very old, most Americans know where they belong in the system. As a consequence of the dominance of the major parties, most elected officials are either Republicans or Democrats. Attempts to break up this old political system have been made in every presidential election in the past one hundred years, but the system has survived all assaults.
How does it happen that the system is so strongly rooted in American politics The explanation is probably to be found in the way elections are conducted. In the United States, unlike countries with a parliamentary system of government, we elect not only the President, but a large number of other officials. We also elect congressmen from single-member districts.
A. The election system of America.
B. The American two-party system.
C. The struggle between the two major parties in America.
D. The advantage and disadvantage of American political system.