A.Playing classical music.

　　B.Introducing lemon scent.

　　C.Making the light brighter.

　　D.Using plates of larger size.

3.What does the last paragraph talk about?

　　A.Tips to attract more customers.

　　B.Problems restaurants are faced with.

　　C.Ways to improve restaurants' reputation.

　　D.Common misunderstandings about restaurants.

　　Chimps(黑猩猩) will cooperate in certain ways, like gathering in war parties to protect their territory. But beyond the minimum requirements as social beings, they have little instinct (本能) to help one another. Chimps in the wild seek food for themselves. Even chimp mothers regularly decline to share food with their children, who are able from a young age to gather their own food.

　　In the laboratory, chimps don't naturally share food either. If a chimp is put in a cage where he can pull in one plate of food for himself or, with no greater effort, a plate that also provides food for a neighbor in the next cage, he will pull at random-he just doesn't care whether his neighbor gets fed or not. Chimps are truly selfish.

　　Human children, on the other hand, are naturally cooperative. From the earliest ages, they desire to help others, to share information and to participate in achieving common goals. The psychologist Michael Tomasello has studied this cooperativeness in a series of experiments with very young children. He finds that if babies aged 18 months see an unrelated adult with hands full trying to open a door, almost all will immediately try to help.

There are several reasons to believe that the urges to help, inform and share are not taught,but naturally possessed in young children.One is that these instincts appear at a very young age before most parents have started to train their children to behave socially. Another is that the helping behaviors are not improved if the children are rewarded. A third reason is that social intelligence develops in children before their