阅读理解。

1. Trees can get light from _____ in the daytime.

A. CO2

B. O2

C. the sun

2. Chlorophyll is in _____.

A. sunlight

B. soil

C. leaves

3. We can get more O2 by _____.

A. planting more trees

B. cutting trees down

C. making the water in soil polluted

4. CO2from air and _____ can produce food for trees with the help of chlorophyll and sunlight.

A. water in the sea

B. water from soil

C. water in the river

5. The picture tells us _____.

A. how trees let O2 go into air in the sunlight

B. how trees let CO2 go into air in the sunlight

C. the sunlight isn't important to trees at all