12. Land pollution happens when human activities ___________ the Earth’s surface.

A. cover                      B. destroy                   C. damages                 D. cause

13. Noise pollution occurs ___________ there are too many loud sounds in the environment.

A. while                      B. and                         C. because                   D. so

14. The sight of too many telephone poles, advertising billboards, overhead power lines, or shop signs may cause ___________ pollution.

A. visual                      B. vision                      C. visualize                  D. visible

15. People don’t care much about the environment, so they keep ___________ it worse.

A. made                      B. making                    C. to make                   D. make

16. She suffered ___________ a serious disease because of drinking contaminated water for a long time.

A. in                            B. at                            C. to                            D. from

17. The roads were slippery ___________ it started to rain.

A. so                            B. as soon as              C. when                       D. before

18. We hope more people join our ___________ programme.

A. environment           B. environmental         C. environmentalist     D. environmentally

19. Harmful gases like nitrogen oxides and sulphur oxides are ___________ into the atmosphere during the burning of fossil fuels.

A. releases                   B. released                  C. release                     D. releasing

20. The ___________ of air pollution are alarming.

A. effective                 B. affect                      C. effect                      D. effects