試題詳解

2. In paragraph 2, why does the author include the information that dinosaurs had flourished for tens of millions of years and then suddenly disappeared?
(A) To support the claim that the mass extinction at the end of the Cretaceous is the best-documented of the dozen or so mass extinctions in the geological record
(B) To explain why as many as half of the species on Earth at the time are believed to have become extinct at the end of the Cretaceous
(C) To explain why paleontologists have always been intrigued by the mass extinction at the end of the Cretaceous
(D) To provide evidence that an impact can be large enough to disturb the environment of the entire planet and cause an ecological disaster