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.
Life was slow to settle upon the Galapagos Islands because the______.

选项 A、land cooled slowly
B、islands were far from other islands
C、islands were very small
D、both A and B

答案D

解析 文中第二段第一句说:“数千年过后生物能够在冷却的群岛上安定下来。”第二段第四句说:“南美大陆距该群岛有600多英里远,任何动物远涉重洋后,能够存活下来的机会都很小,只有为数不多的顽强的物种存活了下来。”由此可见,选项A和B都符合文章内容,所以正确答案应为D。
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