The C0₂ flooding system is actuated by a sequence of steps which are（）.

A.break glass，pull valve，break glass，pull cylinder control

B.sound evacuation alarm，pull handle

C.open bypass valve，break glass，pull handle

D.open stop valve，open control valve，trip alarm

在脚手架使用期间，应禁止（）。

A.松动或拆除任何受力杆件

B.增加受力杆件

C.增加脚手板

D.与桥墩拉结