What was one of Martin Luther King Jr.'s significant contributions?

One of Martin Luther King Jr.'s most significant contributions was his fight for civil rights. He played a crucial role in the American civil rights movement from the mid-1950s until his assassination in 1968. King is best known for advocating nonviolent resistance to combat racial discrimination and social injustice. His leadership during events such as the Montgomery Bus Boycott, and the March on Washington, which included his famous "I Have a Dream" speech, helped to raise awareness of civil rights issues and pushed for the passage of landmark legislation like the Civil Rights Act of 1964 and the Voting Rights Act of 1965. His work not only transformed the conversation around civil rights in the United States but also inspired movements for social justice across the globe.

The other choices do not encapsulate King's main legacy as effectively as his commitment to civil rights. While he may have had indirect influences in those areas, the core of his impact lies in his dedication to racial equality and justice.