—Two hundred of the tourists were saved from danger in Taiwan, but the rest ______ still missing.  

—If the travel agency ______ more safety measures, this accident could have been avoided.  [ ]

A. is; has taken

B. are; had taken

C. were; had taken    

D. are; would take

立克次体病（）

A.中毒性菌痢

B.流行性乙脑

C.霍乱

D.伤寒

E.斑疹伤寒