题目

A woman from Japan, who had visited major businesses and investment companies in New York City, was telling a friend about her trip to the US. I studied English before I left home. But I still was not sure that people were speaking English. Her problem is easy to understand. Americans in business are like people who are in business anywhere. They have a language of their own. Some of the words and expressions deal with the special areas of their work. Other expressions are borrowed from different kinds of work such as the theater and movie industry. One such saying is get your act toget细胞学说建立于19世纪，是自然科学史上的一座丰碑。它揭示了 A．细胞的统一性                  B．细胞的多样性  C．植物细胞与动物细胞的区别      D．细胞分化的根本原因