Sometimes you may have a strong desire to do something strange or terrible. However, chances are that you don't act on your impulse  , but let it pass instead. You know that to take the action is wrong in some way and that other people will not accept your behavior. Perhaps the most interesting thing about the phenomenon of _ behavior is how it can change over the years, how certain behavior and attitudes once considered taboo can become perfectly acceptable and natural at another point in time. Topics such as death, for example, were once considered so upsetting that it was a taboo to even talk about them. Now with the publication of important books such asOn Death and DyingandLearning to Say Goodbye, people have become more aware of the importance of expressing feelings about death and, as a result, are more willing to talk about this taboo subject. One of the newest taboos is the topic of fat. Unlike many other taboos, fat is a topic that people talk about constantly. It's not taboo to talk about fat; it's taboo to be fat. The _ is thin, not fat. In the work world, most companies prefer youthful-looking, slim manager to sell their image as well as their products to the public. The thin look is associated with youth, vigor, and success. The fat person, on the other hand, is thought of as lazy and lacking in energy, self-discipline and self-respect. After all, how can people permit themselves to become fat? In an image-conscious society, thin is ''in", fat is "out". It' s not surprising that millions of people have become obsessed   with staying slim and "in shape". The pursuit of a youthful physical appearance is not, however, the only reason for people's obsession with diet and exercise. Recent research has shown the importance of diet and exercise for personal health. As in most technologically developed nations, the life-style of people has changed since last century. Modern machines do all the physical labor. Cars and buses transport us quickly from point to point. As a result of inactivity and disuse, people's bodies can easily become weak. In an effort to avoid such a fate , millions of people are spending more of their time exercising. Parks are filled with joggers and bicyclists, and many companies are providing special exercise equipment for their employees to use during the work day. What does the word "taboo'' refer to in the passage?
Behavior considered unacceptable to the society. An unfavorable impression left on other people. A strong desire to do something strange or terrible. A crime committed on impulse.