题目内容：
第50题___________
A．But life on the Caribbean Islands is not always paradise. B．The earliest name used by Europeans is the Indies, later changed to the West Indies.
C．They're like a long necklace that stretches between North and South America.
D．They are Cuba, Puerto Rico, Jamaica, and Hispaniola.
E．This is why millions of tourists visit the islands each year.
F．Some of these islands are no more than tiny slivers (小片) of exposed coral.
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答案解析：