Which compromise established a bicameral legislature in the United States?

The Great Compromise, also known as the Connecticut Compromise, established a bicameral legislature in the United States during the Constitutional Convention of 1787. This compromise balanced the needs of states with large populations and those with smaller populations by creating a two-house legislature: the House of Representatives and the Senate.

In the House of Representatives, representation is based on each state's population, which benefits larger states, while in the Senate, each state is given equal representation with two senators, which ensures that smaller states have an equal voice in the legislative process. This structure was critical for fostering unity among the states and addressing the differing interests that were present at the time, thus facilitating the passage of the United States Constitution.

The other options focus on different historical issues. The Missouri Compromise dealt with the regulation of slavery in the western territories, the Compromise of 1850 involved various measures to resolve sectional tensions around slavery, and the Three-Fifths Compromise addressed how slaves would be counted for purposes of taxation and representation. None of these compromises established the legislative framework that the Great Compromise did.