A consumer's net gain is the difference between the price a consumer is willing to pay in order to obtain a commodity and the actual price he or she pays to obtain the commodity. Consumer net income measures the additional benefits that buyers feel they are getting.
By definition, which of the following options reflects the net benefit to the consumer?
Ms. Li just paid this month's salary of 4000 yuan, ready to spend all the money to buy clothes, after the weekend shopping mall, found that there are still 1000 yuan