Read the text and answer the question by selecting all the correct responses. More than one response is correct.

There is increasing proof that the impacts of meteorites have had important effects on Earth, particularly in the field of biological evolution. Such impacts still create a natural hazard to life on Earth. Twice in the 20th century, giant meteorite objects are known to have collided with Earth. If a bearing is large enough, it can disturb the environment of the whole Earth and cause an ecological catastrophe. Around 65 million years ago, the best-documented such impact took place at the end of the Cretaceous period of geological history. This break in Earth’s history is marked by a mass extinction when as many as 0.5% the species on the planet became extinct. Whereas there are more mass extinctions in the geological record, the Cretaceous mass extinction has forever intrigued paleontologists. As a result, it marks the end of the age of the dinosaurs. For 10 million years, those great creatures had flourished. Then, suddenly, they disappeared.

Q. 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

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