According to paragraph 1, which of the following is true of the Late Cretaceous climate?

• (A) Summers were very warm and winters were very cold.

• (B) Shallow seas on the continents caused frequent temperature changes.

• (C) The climate was very similar to today’s climate.

• (D) The climate did not change dramatically from season to season.

Which of the following reasons is suggested in paragraph 2 for the extinction of the dinosaurs?

• (A) Changes in the lengths of the days and nights during the Late Cretaceous period

• (B) Droughts caused by the movement of seaways back into the oceans

• (C) The change from mild to severe climates during the Late Cretaceous period

• (D) An extreme decrease in the average yearly temperature over 10,000 years

Why does the author mention the survival of “snakes, lizards, turtles, and crocodiles” in paragraph 3?

• A) To argue that dinosaurs may have become extinct because they were not cold-blooded animals

• (B) To question the adequacy of the hypothesis that climatic change related to sea levels caused the extinction of the dinosaurs

• (C) To present examples of animals that could maintain a livable body temperature more easily than dinosaurs

• (D) To support a hypothesis that these animals were not as sensitive to climate changes in the Cretaceous period as they are today

The word “cope” in the passage is closest in meaning to

• (A) adapt

• (B) move

• (C) continue

• (D) compete

According to paragraph 3, which of the following is true of changes in climate before the Cretaceous period and the effect of these changes on dinosaurs?

• (A) Climate changes associated with the movement of seaways before the Cretaceous period did not cause dinosaurs to become extinct.

• (B) Changes in climate before the Cretaceous period caused severe fluctuation in sea level, resulting in the extinction of the dinosaurs.

• (C) Frequent changes in climate before the Cretaceous period made dinosaurs better able to maintain a livable body temperature.

• (D) Before the Cretaceous period there were few changes in climate, and dinosaurs flourished.

The word “fluctuations” in the passage is closest in meaning to

• (A) extremes

• (B) retreats

• (C) periods

• (D) variations

Which of the sentences below best expresses the essential information in the highlighted sentence in paragraph 4? Incorrect choices change the meaning in important ways or leave out essential information.

• (A) The fossil record suggests that there was an abrupt extinction of many plants and animals at the end of the Mesozoic era.

• (B) Few fossils of the Mesozoic era have survived in the rocks that mark the end of the Cretaceous.

• (C) Fossils from the Cretaceous period of the Mesozoic up to the beginning of the Cenozoic era have been removed from the layers of rock that surrounded them.

• (D) Plants and animals from the Mesozoic era were unable to survive in the Cenozoic era.

In paragraph 4, all the following questions are answered EXCEPT:

• (A) Why is there a layer of clay between the rocks of the Cretaceous and Cenozoic?

• (B) Why were scientists interested in determining how long it took to deposit the layer of clay at the end of the Cretaceous?

• (C) What was the effect of the surprising observation scientists made?

• (D) Why did scientists want more information about the dinosaur extinctions at the end of the Cretaceous?

The word “bombard” in the passage is closest in meaning to

• A) approach

• (B) strike

• (C) pass

• (D) circle

Paragraph 5 implies that a special explanation of the Ir in the boundary clay is needed because

• A) the Ir in microscopic meteorites reaching Earth during the Cretaceous period would have been incorporated into Earth’s core

• (B) the Ir in the boundary clay was deposited much more than a million years ago

• (C) the concentration of Ir in the boundary clay is higher than in microscopic meteorites

• (D) the amount of Ir in the boundary clay is too great to have come from microscopic meteorites during the time the boundary clay was deposited