Many experts considered _________ quite necessary for the people in the earthquake-hit areas to be

given a lecture on psychological comfort.[ ]

A. that

B. it

C. this

D. one

提高顾客认知价值的途径有（）。

A．提高产品质量

B．加强售后服务

C．节省顾客购买时间

D．提高顾客对产品效用的期望值

E．加大产品销售时的价格折扣