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In paragraph 3, why does the author include the information that a large amount of soot is found in sediment from 65 million years ago? A. To identify the largest component of the dust sent into the atmosphere by the impactor's crash B. To support the idea that the impactor's crash probably caused widespread wildfires C. To emphasize the large variety of substances found in the sediment D. To cast doubt on the claim that the impact affected only the area near the crash site