One reason the united states has a two-party system is
a. the constitution created the two-party system.
b. americans share few of the same basic ideals, principles, and beliefs.
c. the nation has sharp political divisions based on economic class, social status, and national origin.
d. much of american election law is written to discourage non-major party candidates.

The correct answer is d, much of an American election law is written to discourage non-major party candidates.

Explanation:

The United States has two-party system, where the Republican and Democratic parties hold most of the elected offices, and third parties have a very slim chance of winning any elections. According to French political scientist Maurice Duverger, this is because of the winner-takes-it-all electoral system of the United States. Under this electoral law, candidates who get the most votes in an election win their seats, while losing candidates get nothing at all. This arrangement means that voters will tend to support candidates who have realistical chances of winning, ie. those from the two major parties.

answer; i believe its called ; checks   and balances;