题目内容：

    We all know that foods will easily go bad if they get too warm. So we usually put them into our fridges to keep cool in hot weather. But can you make it without fridges?

In 1995，Abba，a teacher from Nigeria，found a cool way. His invention was called Pot-in-Pot Cooling System.

It uses two clay pots (陶罐). There is a smaller pot inside a lager one. The space between the two pots is filled with wet sand. Some foods can be kept fresh for several weeks in it.

Abba built five thousand pot-in-pot systems for the villagers in his hometown. Then people all over the country began using the invention. Soon it became popular with farmers in other African countries.

In 2000, Abba got a prize--the Rolex Award. If you are trying to do something to improve human life，you may have the chance to get this prize.

根据短文内容，选择最佳答案。

1.______from Nigeria invented the Pot-in-Pot Cooling System.

A.A teacher B.A cook C.A scientist D.A worker

2.In the Pot-in-Pot Cooling System, you should put fruit and drinks ______.

A.under the wet sand B.outside the larger pot C.between the two pots D.inside the smaller pot

3.Abba built five thousand pot-in-pot systems to help ______in his hometown.

A.his family B.his students C.the villagers D.the school

4.Many farmers in African counties used Abba’s invention to ______.

A.store wet cloth B.get warm C.keep foods fresh D.win a prize.