Legal challenges through the courts was primarily used by the civil rights movement in the 1950s and 1960s.
Option C
Explanation:
The "civil rights movement" was led by group people like Martin Luther King Jr., Malcolm X, the Little Rock Nine, and many others. The main approach used during the civil rights movement was protests and nonviolent marches.
By adopting the idea of nonviolent protest, the civil rights movement of the 1950s and '60s removed the model of public facilities' being separate out by race in the South and accomplished the most important achievement in equal-rights legislation for African Americans since the Reconstruction period from "1865 to 1877".