Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 37 to 43.
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 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 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.
According to the passage, some researchers suggest that mammoths became extinct
Đáp án B
Dựa vào đoạn văn, một vài nhà nghiên cứu gợi ý rằng voi ma mút tuyệt chủng vào ________.
A. khoảng 2000 năm trước
B. khoảng 4000 năm trước
C. khoảng 7000 năm trước
D. khoảng 10000 năm trước
Giải thích: “The scientists have reported that the beasts may have survived until 2000 B.C. on an island off the coast of Siberia, where researchers uncovered 29 fossilized woolly mammoth teeth ranging in age from 4,000 to 7,000 years.” (Họ cho rằng những con quái vật này có thể vẫn còn tồn tại cho đến năm 2000 Trước công nguyên trên đảo ngoài khơi Siberia, nơi nhà nghiên cứu khám phá 29 hoá thạch răng voi ma - mút lông xoăn từ 4,000 đến 7,000 năm tuổi) => tuyệt chủng 4000 năm trước