Since January 2013, there have been more “smog” weather conditions in Beijing (as shown in the picture). All domestic parties are very concerned about the capital’s air quality. The Beijing Environmental Protection Bureau has proposed

A. Increase efforts to replace coal with electricity and gas, and promote the use of clean energy, which can improve air quality;

B. Increase efforts to renew old motor vehicles and improve exhaust emissions Emission standards can improve air quality;

C. Reduce students’ outdoor exercise time to avoid respiratory diseases, which has nothing to do with improving air quality;

D. Do a good job in dust control and management at construction sites , can improve air quality.

So choose C.