根据对话内容，从对话后的选项中选出能填入空白处的最佳选项。选项中有两项为多余的选项.

A:    1   :

B:  Only once. I went to see my uncle who lives in Guangzhou. I found it so interesting and so

    different from Hong Kong.

A:     2   

B:  No. Nearly everyone rides a bike. There are more cars in Guangzhou than in most other Chinese

     cities, but still far fewer than here.

A:  Riding bikes can keep people healthy.

B:    3   It's certainly better exercise than sitting in a car.

A: They must have many buses in Guangzhou, too. don't they?

B:    4   It's very noisy in the rush hours when people are coming and going from work. The ringing

    of bike bells and the bust's blowing the horns( 喇叭) make a terrible noise.

A:   5  

A. How often do you go to China?

B. I was told there aren't many cars.

C. Have you ever been to China?

D. It can't be much noisier than Hong K

E. Of course they do.

F. I don' t think so.

G. I suppose it does.