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, based on the fact that the meteorite can best explain the sudden appearance of high concentrations of the element iridium, which is found in meteors and, in and of itself, in no way related to changes in the terrestrial climate.

A in the Earth’s climate alone, based on the fact that the meteorite can best explain the sudden appearance of high concentrations of the element iridium, which is found in meteors

B in the Earth’s climate alone—changes that can best be explained by the sudden appearance of high concentrations in iridium, an element that is found in meteors

C to the climate of the Earth, and this best explains the sudden appearance of iridium, an element in high concentrations in meteors
in the Earth’s climate alone

D in the Earth’s climate alone; the former best explains the sudden appearance of high concentrations of iridium, an element found in meteors

E 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
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