Difficult to Have Hard DiscoveriesIf there is one thing scientists have to hear, it is that the game is over. Raised on the belief of an endless voyage of discovery, they recoil (畏缩) from the suggestion that most of the best things have already been located. If they have, today"s scientists can hope to contribute no more than a few grace notes to the symphony of science.A book to be published in Britain this week,The End of Science, argues persuasively that this is the case. Its author, John Horgan, is a senior writer forScientific American magazine, who has interviewed many of today"s leading scientists and science philosophers. The shock of realizing that science might be over came to him, he says, when he was talking to Oxford mathematician and physicist Sir Roger Penrose.The End of Scienceprovoked a wave of denunciation (谴责) in the United States last year. "The reaction has been one of complete shock and disbelief," Mr. Horgan says.The real question is whether any remaining unsolved problems, of which there are plenty, lend themselves to universal solutions. If they do not, then the focus of scientific discovery is already narrowing. Since the triumphs of the 1960s—the genetic code, plate tectonics (板块构造学说), and the microwave background radiation that went a long way towards provingthe Big Bang—genuine scientific revolutions have been scarce. More scientists are now alive, spending more money on research, than ever. Yet most of the great discoveries of the 19th and 20th centuries were made before the appearance of state sponsorship, when the scientific enterprise was a fraction of its present size.Were the scientists who made these discoveries brighter than today"s That seems unlikely. A far more reasonable explanation is that fundamental science has already entered a period of diminished returns. "Look, don"t get me wrong," says Mr. Horgan. "There are lots of important things still to study, and applied science and engineering can go on forever. I hope we get a cure for cancer, and for mental disease, though there are few real signs of progress." Which of the following statements may be true according to the passage

A. Great scientific discoveries will never be possible.
B. The harsh challenge has to be met by modem scientists.
C. The state sponsorship and scientific enterprise are all in vain.
D. The chance for great scientific discoveries becomes scarce.