单项选择题
Passage One Questions 26 to 28 are based on the passage you have just heard.
A. It first appeared in 1988. B. It traveled via e-mail messages. C. It first broke out in Britain. D. It was meant to steal documents.
A. among B. across C. through D. from
A. It may not bring huge profits for companies. B. It has become a new field of scientific research. C. It means a heavy investment for companies. D. It is necessary for the success of new products.