题目内容：

According to the studies from the UN, the increase of CO2 in the air is responsible for 85% of the temperature increase. CO2 goes into the air when we burn fossil fuels to run our industries, cars and so on. Luckily, half of the CO2 that we produced is taken in by plants, trees, land and the oceans. The rest gases are still large to cause worry. At the same time, we are cutting down forests that take in carbon from the air.

To solve the problem is not an easy job. Developed nations such as the USA, Germany and Australia will have to promise to cut down greenhouse gases by as much as 25-40%. Countries such as India and China that have a large population and growing industry, have to leave a smaller greenhouse gas footprint. Everybody must be active and stick to it.

1. Half of the CO2 that we produced can be taken in by ___________.

A. plants and trees       B. land

C. the oceans             D. A, B and C

2. Why does the temperature increase?

A. People use up useful gases.

B. More and more CO2 goes into the air because of people’s activities.

C. Forests can not take in CO2 any more.

D. Everybody hopes winter can be warm.

3.How many countries are mentioned in this passage?

A. 2               B. 3               C. 5             D. 6