Q:BEIJING, Feb. 26 (China Daily) -- As the smog orange warning continues, tourist attractions in Beijing are experiencing a significant decline in visitor number. A new report launched by Beijing authorities on the morning of February 24 indicates that the concentration of PM 2.5 has risen, with no sign of decreasing, the orange warning will still be in effect, according to Xinhua News Agency. According to data released by the Beijing Tourism Website, by 2:00 pm, February 24, popular tourist attractions including The Great Wall and Palace Museum had been affected by the smog in terms of tourist numbers. As for the Palace Museum, the number of visitors was only 11,200 that day, far from the figure of 40,000, which is the daily average number of visitors it normally receives. There were a few visitors in Beihai Park on the morning of February 24, and two visitors from Hebei province planned to end their morning tour earlier than scheduled because of the smog. One of them said, "The visibility is so poor that we can't take good photos, or even see clearly. We'd better leave early." In response to worsening air conditions, travel agencies have also taken some measures to avoid a further decline in tourist numbers. An employee with China Youth Travel Service, Wang Tao, said the agency will inform tourists of the weather conditions at their destinations. A tour guide with China Travel Service also told the media that it was a tour guide's duty to inform foreign visitors of the smog conditions in Beijing, and the agency will provide free face masks to those in need. But _ , because the root cause is air pollution. China will introduce various emergency responses and long-term measures against air pollution. Officials and experts called for combined efforts by governments, industries and the public to cooperate more efficiently and to jointly solve the problem. The most effective way to solve the problem of air pollution is to _ . A) take some measures of treating the symptom merely B) unite the power of governments, industries and the public C) provide free face masks to those in need D) inform tourists of the weather conditions at their destinations
A:
B