问题详情

We can learn from the first paragraph that ______.

A．people are getting much richer than before

B．it"s necessary for people to accept the concept of exchanging the money for something of comparable value

C．there is a decline in product quality that people have to renew them all the time

D．commercials are making us happier and more content

请帮忙给出正确答案和分析，谢谢！