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A team of Russian scientists has challenged the theory that the woolly mammoths became extinct 10,000 years ago at the end of the Ice Age. The scientists have reported that the beasts may have survived until 2000 B.C. on an island off the coast of Siberia, where researchers 5 uncovered 29 fossilized woolly mammoth teeth ranging in age from 4,000 to 7,000 years. The question to be asked now is, how did these prehistoric pachyderms survive in their island environment? One possibility is that they adapted to their confined surroundings by decreasing their bulk. This theory is based on their smaller tooth size, which 10 has led scientists to believe that they were only 6 feet tall at the shoulder compared with 10 feet of their full-sized counterpart. But would this be enough to enable them to survive thousands of years beyond that of other mammoths? Researchers are still working to uncover the reasons for this isolated group’s belated disappearance.

1. With which topic is this passage mainly concerned?

2. According to the passage, some researchers suggest that mammoths became extinct

3. The word “woolly” as used in line 1 refers to the animal’s

4. The word “uncovered” as used in line 5 is closest in meaning to which of the following?

5. The word “adapted” in line 8 could best be replaced with

6. In line 8, the word “confined” could best be replaced by

7. The author uses the word “counterpart” in line 11 to refer to

8. The word “enable” in line 12 could best be replaced by which of the following?

9. The word “belated” in line 14 is closest in meaning to which of the following?

10. According to the scientists, the woolly mammoths may have managed to survive because they

11. According to the passage, the reason for the disappearance of the mammoths on the island is

12. Which of the following terms from the passage is NOT used to refer to the mammoths?