足月儿生理性贫血一般发生在
A．出生后1周
B．出生后1—2个月
C．出生后2—3个月
D．出生后3—4个月
E．出生后6个月
参考答案：C
太阳活动增强时，地球上相应的变化是[ ]
A、南极冰山融化速度增快
B、地球上火山地震频发
C、南极上空臭氧空洞明显增加
D、无线电短波通讯受到强烈干扰
---_____book is this?
--- I think it _____ Carla’s. It has his name on it.
A．Who is, could be
B．Who’s, might belong to
C．Whose, must be
D．Whose, can’t belong to
