There were dirty marks on her trousers__________she had wiped her hands.

A.  where        B.  which        C.  when      D.  that

There were dirty marks on her trousers ______ she had wiped her hands.

      A. where                  B. which                 C. when                    D. that

 There were dirty marks on her trousers _________ she had wiped her hands.

       A. where            B. which                C. when              D. that

There were dirty marks on her trousers _______ she had wiped her hands.

A. where B. which     C. when D. that