选择题：According to the passage, the earth in its very early period was ______.

题目内容：

According to the passage, the earth in its very early period was ______.

A. in molten state

B. in water state

C. in rock state

D. a vast ocean

参考答案：

直挂云帆济沧海。直:

直挂云帆济沧海。直：

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