Because she was ill yesterday, ________ she didn’t come to school.

1. A.
   so
2. B.
   but
3. C.
   and
4. D.
   /

Because she was ill yesterday, ________ she didn’t come to school.

[　　]

Betty didn't come to school yesterday ________ she was ill．

1. A.
   but
2. B.
   than
3. C.
   if
4. D.
   because