_______we admit that there are still some problems about NMET,we don’t mean that it is of no use.

A.Until          B.While         C.As                     D.Unless

_________ we admit that there are still some problems about NMET, we don't mean that it is of no use.

A. Until     B. While            C. As         D. Unless

___we admit that there are still some problems about NMET, we don't mean that it is of no use.

A. Until                B. While                      C. As                           D. Unless

___we admit that there are still some problems about NMET, we don’t mean that it’s of no use.

_______we admit that there are still some problems about NMET,we don’t mean that it is of no use.

1. A.
   Until
2. B.
   While
3. C.
   As
4. D.
   Unless