He waited with his companion_________the rescuers came, and then helped them carry her back down the mountain.

1. A.
   when
2. B.
   until
3. C.
   unless
4. D.
   while

 He waited with his companion_________the rescuers came, and then helped them carry her back down the mountain.

   A. when              B. until             C. unless           D. while

He waited with his companion_________the rescuers came, and then helped them carry her back down the mountain.

 He waited with his companion        the rescuers came, and then helped them carry her back down the mountain.

   A. when              B. until             C. unless           D. while