血浆中含有抗A和抗B凝集素的血型是
A．A型B．B型C．O型D．AB型E．Rh阳性
参考答案：C
—It’s already nine o’clock.Would now be a(n) moment to show the sides?
—OK,go ahead please.
A．necessary
B．gradual
C．suitable
D．important
简述问卷的基本结构。
