题目

Beijing's broadened ban on smoking in public places took effect Thursday, adding force to the effort to hold a smoke-free Olympics. The new rules extend existing anti-smoking regulations to more places, including fitness centers, cultural relic sites, offices, meeting rooms, dining halls, toilets and lifts. Restaurants, Internet cafes, parks, and waiting halls at airports, railway stations and coach stations are required to set up smoking areas. Hotels will have to offer smoke-free rooms or floors, but the regulations do not specify a proportion.     However, some restaurant owners have com有些重大交通事故，是由于大雾引起的汽车追尾，雾属于下列哪种分散系（　　）A．乳浊液B．溶液C．胶体D．悬浊液