TOEFL Reading: ETS-TOEFL阅读机经 - 8G3MWWR8GU1CM3QZL$

According to paragraph 3, what information did scientists use to predict the size of the impactor that they believed struck Earth 65 million years ago? A. The size of the debris found in geological samples from that time B. The distance inland that traces of tidal waves were found C. The amount of iridium found in sediment from that time D. The number of species that became extinct at that time