Ancient china was a place _____ states were often at war with each other.[ ]

A. that    

B. where  

C. when  

D. what

补体促进吞噬细胞的吞噬作用被称为补体的()

A.炎症介质作用 

B.调理作用 

C.免疫粘附作用 

D.溶菌和细胞毒作用 

E.中和及溶解病毒作用