15. Which of the following sentences does Martin Luther King, Jr., use in his "I Have a Dream" speech to encourage future optimism? O A. "This is no time to engage in the luxury of cooling off or to take the tranquilizing drug of gradualism."
B. "With this faith, we will be able to hew out of the mountain of despair a stone of hope."
O C. "We can never be satisfied as long as the Negro is the victim of the unspeakable horrors of police brutality."
O D. "One hundred years later, the Negro lives on a lonely island of poverty in the midst of a vast ocean of material prosperity."