一般初孕妇开始自觉胎动的时间是在妊娠的（）。
A.12～16周
B.18～20周
C.22～24周
D.25～26周
E.27周以后
参考答案：B
反应型气孔
These causes produced the great change in the country that modernized the______of higher education from the mid-1860s to the mid-1880s.
A．branch B．category C．domain D．scope
