— Who should be responsible for the accident?                                             

— The boss, not the workers. They just carried out the order _____.  [ ]

A. as told  

B. as are told  

C. as telling  

D. as they told.

在牙周炎中以B淋巴细胞浸润为主的阶段是（）

A.病损确立期

B.进展期

C.早期病变

D.始发期

E.修复期