15．I didn’t see your sister at the meeting. If she _______, she would have met my brother.

A．has come

B．did come

C．came

D．had come

患者，男性，40岁，溃疡病合并幽门梗阻，长期呕吐可引起（）

A.低钾低氯性代谢性碱中毒

B.高钾低氯性代谢性碱中毒

C.低钾高氯性代谢性碱中毒

D.高钾高氯性代谢性碱中毒

E.低钾低氯性呼吸性碱中毒