With so many people _____ by send e-mails every day, it will become more and more important to have _____

knowledge of computer. [ ]

A. communicating; a good

B. communicated; good

C. communicating; good

D. communicated; a good

“夜市喧至三更尽，才五更又复开张。如耍闹去处，通晓不绝”，“天街买卖，直至五鼓，玩月游人，婆娑于市，至晓不绝”，“茶坊每五更点灯，博易买卖衣物、图画、花环、领抹之类，至晓即散，谓之鬼市子”。材料中描绘的这种经济现象出现在(　　)

A．西汉

B．隋唐

C．北宋

D．元朝