Paper money was in use in China when Marco Polo visited the country in thirteenth centur

Paper money was in use in China when Marco Polo visited the country in thirteenth century.
A. the; /
B. the; the
C. /; the
D. /; /

A. the; /B. the; the(答案→)C. /; theD. /; /解析：句意：在 马可波罗13世纪到中国来的时候，纸币就在中国使用了。(be) in use 为习惯用语，意思是“在使用中”，不与冠词连用；thirteenth 为序数词，序数词前面通常使用定冠词。选C。

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