21. These are the reasons for smog except _______.

A. industrial activities                 B. fireworks          C. outdoor activities            D. vehicles

22. Florian Kessler considered the pollution had much to do with _________.

A. citizens             B. Chinese government                C. schools                    D. smokers

23. Why do those German companies mentioned in the passage have a hard time?

      A. Because it is hard for them to find staff who like working here.

      B. Because they have kids.                                        C. Because they lack money.

      D. Because Chinese officials don’t like them.

24. Which statement below is NOT TRUE according to the passage?

      A. Smog has affected much of north and central China over the weekend.

      B. Due to smog, schools must stop classes.

      C. Chinese officials didn’t pay enough attention to the environment protection.

      D. Like many other nations, China has to deal with pollution, too.