American culture has not been immune to cultural influences from outside. The idea of demo

cracy came from the ancient Greeks; the Industrial Revolution started in England; jazz and rock music preserve African rhythms—to pick a few examples. Indeed, many of the things we think of as "100 percent American" came from other cultures.

Still, most of the changes in American culture over the last century have come from within, as the result of inventions and discoveries. And change has been dramatic. One hundred years ago the United States was largely a nation of farmers. Many of the things we take for granted today—a high school education, for example, or indoor plumbing—were luxuries then. The moon was a light for lovers, not a site for scientific exploration; genetic engineering (基因工程) was not even a subject for science fiction, much less for laboratory research and corporate investments. The decades following the Second World War, in particular, were characterized by spectacular scientific and technological advances, national self-confidence, optimism, and (for many Americans) prosperity. The American economy was the strongest in the world: more goods were produced and sold, more people were working, and the standard of living was higher than ever before. Polls (民意调查) taken in the 1950s and 1960s show that the average American was preoccupied with the questions "will I make a good living？" "Will I be successful？" and "Will I raise successful, happy children？" Success was defined in terms of maintaining a stable family and "keeping up with the Jones". Most Americans believed that if they played by the rules—if they work hard and did what was expected, if they sacrificed their own needs to those of their family and their employer—they would be rewarded with an ever-increasing standard of living, a devoted spouse, and decent children. An expensive car, a suburban home, and children in college were tangible (可触知的) signs that hard work and self-sacrifice paid off.

Which statement is NOT true according to the passage？

A．There is no 100 percent American culture.

B．American culture has never be influenced by other cultures.

C．America borrowed the idea of democracy from the ancient Greeks.

D．Inventions and discoveries caused the changes within American culture.