The most crucial problem any economic system faces is how to use its scarce resources（　）.

题库:综合类 类型:最佳选择题 时间:2017-07-03 03:10:25 免费下载:《简单单选》Word试卷

The most crucial problem any economic system faces is how to use its scarce resources（　）.
A.puzzling
B.difficult
C.terrifying
D.urgent

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