It is the idea____smiles can get rid of cold ____has been proved by the researchers many times.  

A．which; which

B．that; that

C．that; which

D．which; that

治疗百日咳恢复期肺阴亏虚证的首选方剂是( )

A．人参五味子汤

B．清燥救肺汤

C．沙参麦冬汤

D．生脉散

E．独参汤