采用低频滤波装置时，保留的超声信号来自（）
A.心壁
B.腱索
C.瓣膜
D.血管壁
E.血流
参考答案：E
-----“She's not a dancing teacher, is she?”
------ “_____.”
A．Yes, and she isn't
B．Yes, but she was
C．No, but she isn't
D．No, but she was
下列选项中，属于股权中财产权利的是（）。
A.资产受益权
B.表决权
C.股份转让权
D.剩余财产分配权
