— Laura can't come for dinner. She's leaving for Beijing tonight.   

—  _____. I hope I can talk to her soon.[ ]

A. What a shame  

B. Never mind  

C. Yes, she should  

D. With pleasure

一种商品的价格不可能一成不变，其价格上下波动（　　）

A．使价格长期背离价值

B．是由生产该商品的社会必要劳动时间的不确定性导致的

C．属于不等价交换的表现，违背了价值规律

D．正是价值规律发生作用的表现形式