Answer: A) He uses short sentences to highlight the critical nature of the moment
Explanation: We can automatically rule our B) and C). This is because the text mentions no desire to erase the past, nor does the tone signify that. D) would also not work because Mandela's credibility is not being put in doubt in this article, and his tone does not signify defensiveness of his credibility. That leaves us with A). The repeated sentences all contain contents that point to change, and uprooting a corrupt system, which is urgent.
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