[单项选择题] The loading, unloading, transshipment and transit of inward and outward mail bags are subject to Customs control and a ______ wya bill should be submitted to the Customs by the enterprise providing prviding postal service.
A.cover
B.covering
C.covered
D.haveing covered
正确答案:B


![[单项选择题] The loading, unloading, transshipment and transit of inward and outward mail bags are subjec [单项选择题] The loading, unloading, transshipment and transit of inward and outward mail bags are subjec](http://www.mshxw.com/aiimages/29/602677.png)
