胎盘母体面肉眼观最显著的特点是（）。
A.表面光滑有羊膜覆盖
B.表面有绒毛膜覆盖
C.表面粗糙，可见胎盘小叶
D.有脐带附着
参考答案：C
A series of stimulus policies and supportive measures taken by the government ________ to promote change in the economic environment in this area.
A．are expecting
B．are expected
C．is expecting
D．is expected
事件性投机交易策略主要关注哪些时间变化？
