A smile shows that a person is happy. For example, a person may smile when he or she is pleased with a grade on a test. Or a person might smile if a friend tells a funny joke. People smile for many different reasons. But smiles are more than just a way for people to show that they are happy. 【小题1】

First, it is easier to smile than to show unhappiness. In fact, it only takes 17 muscles (肌肉) to smile. On the other hand, it takes 43 muscles to show unhappiness. 【小题2】

Second, smiles are nice. People may try to look nice on the outside by exercising or wearing nice clothes. As the famous saying goes, “【小题3】” That is because it is easy to be around someone who is smiling and happy. Almost no one wants to be around someone who is unhappy all the time.

Third, smiles have power. 【小题4】 If one person smiles, people around him or her want to smile, too. Similarly, when a person laughs, people tend to laugh with them. If a person is sad, the best thing to do is sharing a smile or laugh. It is the easiest (and cheapest) way to cheer someone up.

【小题5】 Even if you are mad or sad, try smiling. You’ll find that it will be hard to stay mad or sad for very long!

根据材料内容，从下面五个选项中选出能填入文中空缺处的最佳选项，使短文意思通顺、内容完整。

A．A smile is the best thing a person can wear.

B．Both smiling and laughing can easily and quickly spread.

C．There are other good reasons to smile often.

D．Finally, smiling and laughing are very good for the body.

E．So give the muscles in your face a rest and smile!