降低护理成本最为经济的途径是（）
A.物力成本控制
B.人力成本控制
C.实行零缺陷管理
D.零投诉
E.精简人员
参考答案：C
He tells me not only his parents but also he ______America.
A．has been to
B．have been to
C．have gone to
D．has gone to
气胸时叩诊呈 ( )
A．清音B．过清音C．鼓音D．浊音E．实音
