Navigators have known for thousands of years that the ocean has variable currents, but it is only in the last half century that a reasonably clear picture has emerged of the patterns and causes of ocean currents.
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Aa reasonably clear picture has emerged of the patterns and causes of ocean currents
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Ba reasonably clear picture of the patterns of ocean currents and their causes have emerged
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Ca reasonably clear picture emerged of ocean currents, their patterns and the causes of them
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Dthere have emerged a reasonably clear picture of the patterns of ocean currents and what caused them
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Ethere had emerged a reasonably clear picture of the patterns of ocean currents and their causes
分析该选项
显示答案
正确答案: A