49. How did banjihas become important in Seoul?
(A) They could be easily built in Seoul in 1970s with the help of North Korean soldiers.
(B) They were affordable for younger people and poorer people during the housing crisis.
(C) They were low enough for banks in Seoul to handle nation-wide emergencies in 1980s.
(D)They were needed greatly because North Korean commandos needed places to hide themselves.