Read the following paragraphs and then answer the questions: In the wake of air pollution in many Chinese cities, especially in the north, the annual debate over whether Lunar New Year fireworks should be banned has heated up again. According to data from the Ministry of Environmental Protection, 51 out of 338 monitored cities reported pollution levels were “serious” or higher on the Spring Festival Eve. At 2 am on the first day of the Year of the Sheep, 160 cities reported PM2.5 levels above 150mcg/square meter, primarily due to fireworks. Writing in the Beijing Times, commentator Xu Lifan says that there is no legal ground for a complete ban on fireworks during the Lunar New Year holiday because fireworks are not the only source of pollution, and many cities which allowed fireworks didn’t see their pollution levels rise too much. On the other hand, Xu writes, fireworks do pose a serious threat to air quality and people’s personal safety. Therefore, the government should seek to control this by guiding the public to set off fewer fireworks. Such measures include imposing heavy taxes on fireworks and firecrackers and controlling sales in cities that reported serious pollution the year before. The aim of these policies is to try to assign more responsibility to those who create pollution by lighting fireworks, Xu writes. What measure can be taken to guide the public to set off fewer fireworks ?