The correct answer is:
By beginning each sentence of his conclusion with these repeated words, the speaker assists his audience in remembering the summary of his speech.
Explanation:
Great speeches have one thing in common, rhetorical devices. Rhetorical devices are persuasive techniques that add power to the words so the message makes an impact in the audience.
When Nelson Mandela was awarded the Nobel Prize in 1993, he delivered a great speech as a representative of millions of people around the world. His closing lines add a lyrical quality and create a divisive contrast in listeners:
Let it never be said by future generations that indifference, cynicism or selfishness made us fail to live up to the ideals of humanism which the Nobel Peace Prize encapsulates.
Let the strivings of us all, prove Martin Luther King Jr. to have been correct, when he said that humanity can no longer be tragically bound to the starless midnight of racism and war.
Let the efforts of us all, prove that he was not a mere dreamer when he spoke of the beauty of genuine brotherhood and peace being more precious than diamonds or silver or gold.
Let a new age dawn!
The rhetorical device Nelson Mandela used in his closing lines is Anaphora, which is the repetition of a word in a sequence of sentences to achieve a dramatic effect, Nelson Mandela encouraged people through his words to be united and to live up to the ideals of humanism and peace creating a divisive contrast so that future generations would remember them for ending racism and proving Martin Luther King Jr. was right.