A、Emphasize the good quality of his products. B、Emphasize the rarity of his products. C、Emphasize the discount of his products.

In a recent study, shoppers were asked to taste a chocolate-chip cookie. (26) When given a cookie from a full jar, they said it tasted all right; but when they were offered one from a nearly empty jar, they said it tasted better. This shows an interesting aspect of human nature. The scarcer something is, the more highly people tend to value it.
     D. H. Lawrence’s novel Lady Chatterley’s Lover brought the author the most fame not when it was first  published in 1928, (27) but when it was banned -- and when many thousands of black-market copies of the book were sold before it was finally made legal in the 1960s.
     According to social psychologists like Robert Cialdini, our instinctive interest in acquiring things that are rare reflects our evolutionary history. In the past, when food or raw materials were scarce, real value increased, because possession gave the owner an advantage for survival.
    (28) Salespeople love pressing the "scarce, therefore valuable" button, with warnings like "Buy now while stocks last!" and "Quick! Limited-Time Offer!" Clever advertisers know that it’s much more effective to focus on the fear of loss than on the benefit of gain. Experts at the University of California found that homeowners are 300 percent more likely to buy an energy-saving plan if the message is "Stop losing 50 cents a day" instead of "Start saving 50 cents a day". Do you want to make a proposal to your management for a ＄100,000 savings plan? You’re more likely to. get it through if you present your message in terms of a ＄100,000 loss, should your plan not be  accepted.