题目提问,作者暗示现在月球上面的水,结合题干关键词以及第49题的选项,定位到原文:line67-71:And since the moon formed primarily by the wholesale excavation of Earth’s primordial mantle during a collision with another massive object,因此选择A: had its primary source on Earth.
B 轩昂的glass beads,C选项的increase in volume,D选项的liquid form as well as ice form都不符合。
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