TOEFL Reading: ETS-TOEFL阅读机经 - 1TSL534I613NG31BL$

Which of the following is NOT mentioned in paragraph 3 as an effect of the dust raised by the impact 65 million years ago? A. It cooled the surface of Earth. B. It released toxic chemicals into the stratosphere. C. It caused changes in the chemical composition of the atmosphere. D. It prevented sunlight from reaching the surface of Earth.