choose a correct option to form final clauses

1. My father used his dogs____keep wolves away during the night.

   1.   ?    so that
   2.   ?    to
   3.   ?    in order to

2. The airport lit all the lights so that the plane____land safely through the storm.

   1.   ?    can
   2.   ?    should
   3.   ?    could

3. Airbags are special devices____people in car accidents

   1.   ?    for to protect
   2.   ?    for protecting
   3.   ?    so to protect

4. I'll take my own water in case____.

   1.   ?    there wasn't any
   2.   ?    there isn' any
   3.   ?    there shouldn't be any

5. We talked to the secretary ____disturb the boss.

   1.   ?    to
   2.   ?    in order to
   3.   ?    so as not to

6. Please come forward so that your faces____appear visibly in the photograph.

   1.   ?    should
   2.   ?    might
   3.   ?    may