Choose the best options to fill in the blanks in the following sentences

7. While they _ near the river, the flood
A. were camping / was coming
C. was camping/come
suddenly.
B. were camping/came
D. was camping/came
their homework.
B. happened/was doing
8. When the earthquake
they
A. were happening / were doing
C. happened / did
9. When he
dinner, the earthquake
D. happened / were doing
the kitchen.
A. was cooking/was shaking
B. cooked/was shaking
C. was cooking/shook
10. While my mother
D. cooked/shooked
the flowers in the garden, she heard a warning about the coming storm.
A. was watering
B. were watering
C. watered
D. is watering
11. While we
A. was sleeping
a strong earthquake shook the neighborhood.
B. slept
C. were sleeping
D. are sleeping
12. When we
a sudden landslide
on the nearby hill.
A. were camping/ occurred B. was camping / occurred C. camped / occurred D. camped/was occurring