The Event That Threatened to Destroy the Longstanding Balance Between

Multiple Choice

The event that threatened to destroy the longstanding balance between the number of free and slave states in the United States Senate was the

A) passage of the Kansas-Nebraska Act.
B) potential admission of Oregon as a free state.
C) attempt to acquire Cuba as a slave state.
D) proposed building of a southern transcontinental railroad.
E) discovery of gold in California.