Where the Galapagos Islands lie today, there was once an unbroken expanse of Pacific. Then the sea began to seethe and simmer, t

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问题     Where the Galapagos Islands lie today, there was once an unbroken expanse of Pacific. Then the sea began to seethe and simmer, the earth’s crust was pierced, and matter gushed forth continuously. Lava and scoriae (loose, cinderlike lava) piled up until one day spewing volcanoes raised peaks above the brawling sea.
    Many thousands of years passed before life could settle upon the cooled land. Then wind and waves brought the first hardy seed of primitive plants. After these came others, then insects, lizards , and birds. The chance that any animal would survive the trip from the South American continent more than six hundred miles away was slight; only a few hardy species came through alive. This is why there are many gaps in the animal life of the islands.
    Those that did reach the out-of-the-way islands developed over the ages into a number of quite peculiar forms. Because conditions in the Galapagos differed from those in their original homes, the animals had to change or perish. Only in the Galapagos are there seaweed-eating marine lizards, giant tortoises, and flightless cormorants. In fact, most of the species found in the Galapagos Islands are endemics: they exist only in the archipelago.
It is implied in the passage that______.

选项 A、a great evolutionary process took place in the Galapagos Islands
B、only species that are endemic survive in the Galapagos Islands today
C、conditions of life in the Galapagos Islands differed from those in the animals’ original homes
D、the plant life of the Galapagos Islands is endemic

答案A

解析 本题为推断题。文中第三段第二句说:“因为该群岛的生存条件不同于这些动物原来地方的生存条件,为此这些动物不得不改变自己的生活习性,否则就会灭绝。”由此我们可以推断出群岛上的动物遵循了适者生存的法则才存活下来。所以A为正确答案。
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