In ________ now seems the beginning stages of computer history, there was a quite widespread concern ________ computers would take over the world from man one day．

1. A.
   it; that
2. B.
   that; what
3. C.
   it; what
4. D.
   what; that

In        now seems the beginning stages of computer history, there was a quite widespread concern        computers would take over the world from man one day.

A．it; that      B．that; what        C．it; what     D．what; that