题目选项分析

The impact of a large meteor nearly 65 million years ago can better account for the series of cataclysmic events attending the extinction of the dinosaurs than can the concomitant changes to the Earth's climate alone and that the impact can best explain the sudden appearance of high concentrations of iridium in meteors, an element found and, in and of itself, in no way related to changes in the terrestrial climate.

The impact of a large meteor nearly 65 million years ago can better account for the series of cataclysmic events attending the extinction of the dinosaurs than can the concomitant changes in the Earth's climate alone; the former best explains the sudden appearance of high concentrations of iridium, an element found in meteors and, in and of itself, in no way related to changes in the terrestrial climate.