Câu hỏi:

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks from 23 to 27.

University researchers have taken samples from a preserved dodo specimen in an (23)____ to uncover the extinct bird's family tree. They worked with the British Natural History Museum to collect and study genetic material from large number of specimens: a preserved dodo, the extinct solitaire bird, and 35 kind of living pigeons and doves. Their analysis (24)____ the doo and the solitaire to be close relatives with the Nicobar pigeon, their nearest living relative. The dodo lived on Mauritius in the Indian Ocean. It was a flightless bird, bigger than a turkey. By 1681, all dodos had been (25)____by hungry sailors. The solitaire, which looked a bit like a dodo, had gone the same way by 1800. By extracting short pieces of the dodo's DNA and (26) ____ these with the DNA of living birds, the scientists were able to deduce when the dodo evolved away from its relatives into a separate entity. The scientists can now (27)____assume that the dodo developed its distinctive appearance and features as a result of its geographical isolation. They are now convinced that it separated from the solitaire about 25 million years ago, long before Mauritius became an island.

Question 25