钢管脚手架的链接必须用（）。
A.扎篾
B.扣件
C.尼龙绳
参考答案：B
The villagers, _________ had been damaged by the flood, were given help by the Red Cross.
A．all of their homes
B．all their homes
C．whose all homes
D．all of whose homes
处于活动期的狼疮，其辅助检查可能出现（）
A.血沉下降
B.免疫球蛋白下降
C.血清补体C3增加
D.抗核抗体阳性
E.血红蛋白增多
