successful docking of Shenzhou VIII with Tiangong-I means that China has managed to take

successful docking of Shenzhou VIII with Tiangong-I means that China has managed to take first important step to establish its own space station.
A. /; /
B. A; a
C. The, a
D. The; the

A. /; /B. A; aC. The, a(答案→)D. The; the解析：考查冠词。第一空表示特指神州八号与天宫一号的对接，故用定冠词the.第二空序数词前用定冠词the，指走出了重要的第一步.故D正确。

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