It is not just that there is more to do, there is everything to do. What lies ahead, or what can lie ahead if the efforts in basic research are continued, is much more than the conquest of human disease or the improvement of agricultural technology or the cultivation of nutrients in the sea. As we learn more about fundamental processes of living things in general we will learn more about ourselves.

　　52. What CANNOT be inferred from the first paragraph?

　　[A] Scientific experiments in the past three hundred years have produced many valuable items.

　　[B] For three hundred years there have been people holding a hostile attitude toward science.

　　[C] Modern civilization depends on science so man supports scientific progress unanimously.

　　[D] Some people think three hundred years is not long enough to set back for critical appraisal of scientific method.

　　53. The principle discovery in this century shows ________.

　　[A] man has overthrown Newton's laws of physics

　　[B] man has solved a new set of gigantic puzzles

　　[C] man has lost many scientific discoveries

　　[D] man has given up some of the once accepted theories

　　54. Now scientists have found in the past few years ________.

　　[A] the exposure of DNA to the public is unnecessary

　　[B] the tiny cell in DNA is a neat little machine

　　[C] man knows nothing about DNA

　　[D] man has much to learn about DNA

　　55. The writer's main purpose in writing the passage is to say that ________.

　　[A] science is just at its beginning

　　[B] science has greatly improved man's life

　　[C] science has made profound progress

　　[D] science has done too little to human beings

　　56. The writer's attitude towards science is ________.

　　[A] critical [B] approving [C] neutral [D] regretful