[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

　　Passage Two

　　Questions 57 to 61 are based on the following passage.

　　Here amid the steel and concrete canyons, green grass grows. A hawthorn tree(山楂树) stands in new soil, and freshly dug plants bend in the wind.

　　But Chicago City Hall here seems an unlikely spot for a garden of any variety—especially 20,000 square feet of gardens—on its roof.

　　As one of a handful of similar projects around the country, the garden is part of a $1.5 million demonstration projected by the city to reduce its "urban heat islands", said William Abolt, the commissioner of the Department of Environment.

　　Heat islands-dark surfaces in the city, like rooftops-soak up heat. The retention can bake a building, making it stubborn to cooling.

　　The roof of City Hall, a 90-year-old gray stone landmark on LaSalle Street in the heart of downtown, has been known to reach temperature substantially hotter than the actual temperature on the street below.

　　The garden will provide greenery and shade. "And that," said the city officials, "will save the city dollars on those blistering summer days." The project savings from cooling is about $4,000 a year on a new roof whose life span is about 50 percent longer than that of a traditional roof.

　　The sprawling open-air rooftop garden is being carefully built on a multi-tiered bed of special soil, polystyrene, egg-carton-shaped cones and "waterproof membrane" mall to keep the roof from leaking, or caving under the normal combined weight of soil, rain and plant life.

　　The design calls for soil depths of 4 inches to 18 inches. When the last plants and seedlings are buried and the last bit of compost is laid, the garden will have circular brick stepping-stones winding up to hills.