What was a significant contribution of Martin Luther King, Jr.?

A significant contribution of Martin Luther King, Jr. was fighting for civil rights, which played a crucial role in the American civil rights movement during the 1950s and 1960s. He is best known for his commitment to nonviolent resistance as a means to achieve social and racial equality. His leadership in key moments, such as the Montgomery Bus Boycott and the March on Washington, where he delivered his iconic "I Have a Dream" speech, helped to mobilize public opinion and bring attention to the injustices faced by African Americans.

King's efforts were instrumental in the passage of landmark legislation, such as the Civil Rights Act of 1964 and the Voting Rights Act of 1965, which aimed to eliminate legal discrimination based on race. His advocacy emphasized the importance of equal rights and social justice, inspiring countless individuals and movements that have continued to influence civil rights initiatives across the globe.

Although he did touch on other social issues, such as economic justice and opposition to the Vietnam War, his primary legacy is rooted in the fight for civil rights, making this option the most significant in the context of his contributions.