Dichotomy is defined as "a division or contrast between two things that are or are represented as being opposed or entirely different."
Mandela's speech uses dichotomy to emphasize his points as evident in the following excerpt: "We speak here of the challenge of the dichotomies of war and peace, violence and non-violence, racism and human dignity, oppression and repression and liberty and human rights, poverty and freedom from want."
The contrasts mentioned in the speech are: war vs. peace; violence vs. non-violence; racism vs. human dignity; oppression and repression vs. liberty and human rights; and poverty vs. freedom from want. The pairs are negative in opposition to the positive experiences or conditions of human existence.
The answer is D because the information following "message" is the message. A colon is appropriate (as used in D) when the information after the colon describes or represents the word or phrase that comes before the colon.
