Which of the following sentences from Martin Luther King, Jr.'s Nobel Prize acceptance speech best supports the idea that the civil rights movement still has work to accomplish?

A. "Negroes of the United States, following the people of India, have demonstrated that nonviolence is not sterile passivity, but a powerful moral force which makes for social transformation."

B. "Every time I take a flight, I am always mindful of the many people who make a successful journey possible—the known pilots and the unknown ground crew."

C. "I am mindful that only yesterday in Philadelphia, Mississippi, young people seeking to secure the right to vote were brutalized and murdered."

D. "I accept this award on behalf of a civil rights movement which is moving with determination and a majestic scorn for risk and danger to establish a reign of freedom and a rule of justice."