In the past twenty years, the sad father has been to many places-______his lost son.

A．in face of

B．in favor of

C．in charge of

D．in search of

物流中心的发展趋势有（）。

A.科学技术的推动

B.完善城市功能的需要

C.物流环保化

D.物流一体化趋势

E.货运量急剧增加