They have the right to check ______ the will is valid(有效的), of course.

  A. whether         B. why              C. when          D. how

They have the right to check ________ the will is valid(有效的), of course．

1. A.
   whether
2. B.
   why
3. C.
   when
4. D.
   how

They have the right to check ______ the will is valid(有效的), of course.

  A. whether         B. why              C. when          D. how

They have the right to check ______ the will is valid(有效的), of course.

 They have the right to check ______ the will is valid(有效的), of course.

  A. whether         B. why              C. when          D. how