Mrs. Smith finds it hard to clear up the mess, as her children are always ____ whenever she tries to.

A．in the way

B．on watch

C．in sight

D．on the line

使用过量最易引起心律失常的药物是

A．去甲肾上腺素
B．间羟胺
C．麻黄碱
D．多巴胺
E．肾上腺素