What kind of engine did the Hyper-X use? 查看材料
A.A jet engine that carries its own oxygen supply.
B.A jet engine that uses no oxygen.
C.A scramjet engine that doesn't carry its own oxygen supply.
D.A rocket engine that carries its own oxygen supply.

A.A
B.
B.A
C.
C.A
D.
D.A
E.

【参考答案】

C
细节题。利用题干关键词可以定位到文章第二段和第三段最后一句话，可知超音速飞机之所以能达到这么快的速度，是因为......

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