It is obvious that people hold different opinions about ____ voluntary services should be financially rewarded.

1. A.
   that
2. B.
   what
3. C.
   how
4. D.
   whether

It is obvious that people hold different opinions about ____ voluntary services should be financially rewarded.

It is obvious that people hold different opinions about ____ voluntary services should be financially rewarded.

A．that              B．what             C．how              D．whether

 It is obvious that people hold different opinions about ______ voluntary services should be financially rewarded.

A. that             B. what             C. how           D. whether