Then I have learned there are a lot of troubles in our lives, but the problem is __________ they control you or you control them.

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

Then I have learned there are a lot of troubles in our lives, but the problem is __________ they control you or you control them.

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