【正确答案】Despite seductive advertisements, so-called low tar and nicotine cigarettes are really no safer than other cigarettes. The seemingly lower levels of tar and nicotine reported by the Federal Trade Commission are attributable to the FTC use of smoking machines, not human beings, to determine tar and nicotine levels. But people do not smoke like machines. A study of blood samples of smokers found no significant differences among smokers of the various brands and a direct relationship between nicotine intake and the number of cigarettes smoked, regardless of brand.