His ability has never been in doubt ― the question is ______ he is prepared to work hard.
A. whether           B. if
C. that            D. where

His ability has never been in doubt, the question is ________ he is prepared to work hard.

1. A.
   if
2. B.
   that
3. C.
   when
4. D.
   whether

His ability has never been in doubt --- the question is______ he is prepared to work hard.

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

His ability has never been in doubt - the question is ________ he is prepared to work hard.

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