阅读理解。

     Today Newtown is a very clean place. Many years ago, however, there were millions of rats in Newtown.

They attacked (袭击) the cats and dogs. Sometimes a great number of them knocked down a man or woman

walking home at night. The rats were very large in size and they harmed many people. The government ordered everybody to kill rats. Most people were lazy, so they did not kill many.

     Then the government promised to pay some money for each dead rat. That made the people very happy.

They killed thousands of rats every day. A government officer put all the dead rats in a big pile. Sometimes a

man brought hundreds in one day. After two weeks there were not many rats in the city, but people still

brought many rats to the government office. The government officer thought that people were stealing dead

rats from the pile. He ordered his men to dig a deep hole and put the rats in it. Soon there were no more rats

and the government did not pay any more money.

 What would be the best topic for this passage?

A. How Newtown Became a Very Clean Place.

B. How to Kill Rats.

C. Newtown-City of Rats.

D. How Newtown People Became Rich.