_____girls are my friends. [ ]
A. This
B. That
C. His
D. Those
答案：D
不是主动脉瓣关闭不全体征的是
A．Duroziez双重杂音
B．水冲脉
C．Austin-Flint杂音
D．毛细血管搏动征
E．递增型舒张期杂音
简要说明行情预测的局限性。
