Why does Martin Luther King, in his I Have a Dream speech, tell the marchers to Go back Mississippi, go back to Alabama, go back to Georgia, go back to Louisiana, go back to the slums and ghettos of our northern cities?

ATo continue to work for non-violent change in their hometowns.
BTo spread the words of hope and faith.
CTo go back home and dream for the day change will occur.
DTo teach their neighbors the words to "Free at Last".