They stood at the window, ________ they could see ________ was happening in the street.

1. A.
   where; all
2. B.
   which; all
3. C.
   from where; what
4. D.
   from which; that

They stood at the window, _____ they could see _____ was happening in the street.
   A. from which; that B. from where; what   C. where; all     D. where; that  

They stood at the window, ________ they could see ________ was happening in the street.

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