题目

阅读理解     It is common to see many different kinds of insects while spending time outside in the summer. Some of them do not trouble people and can even add beauty to the natural environment. Other insects can harm the environment or humans. The population of these insects seems to stay large and healthy.     But scientists say this does not appear to be true for some flying insects that serve an important purpose. There is growing evidence that these insects are decreasing across the world.     One researcher looking into the present insect population is Doug Tallamy, a professor at the University of Delaware. He remembers walking through Washington D. C., in the past when it was "alive with insects, especially butterflies". Now, he said, "The flying insects are actually gone." Wilson said this point seemed to be proved during a drive he made last year from Boston to Vermont. He was surprised that, during his trip, he counted only one insect that had hit the car's front window. Several other scientists have carried out similar tests by checking how many insects hit their cars while traveling.     While researchers admit this method is not scientific, they say it can still help them understand the changing flying insect population. There have not been many studies done on the flying insect populations covering large areas. However, some international research suggests a downward turn. In 2006, a group of studies showed that there had been a 14-percent drop in ladybugs(瓢虫) in the United States and Canada from 1987 to 2006. In Germany, a 2017 study found an 82-percent drop in the number of flying insects compared to levels recorded in 1990.     After the German study, other countries also started looking into the problem. David Wagner of the University of Connecticut says other evidence leads him to believe the findings of the 2017 study are "clearly not a German thing". （1） The underlined word "this" in Paragraph 2 refers to the fact that _________. A . The insects cause trouble to people. B . The insects harm the environment. C . The insects are numerous and healthy. D . The insects love staying indoors. （2） How does Wilson try to prove the flying insects are gone? A . By making some comparisons. B . By using his personal experience. C . By listing research results. D . By studying the causes. （3） What does David Wagner think of the 2017 German study? A . He considers the study isn't done in German ways. B . He thinks it's less believable than other evidence. C . He considers the German study is a good start. D . He thinks other places also have the problem. （4） In which section of a magazine may this text appear? A . Nature. B . Education. C . Entertainment. D . Health. 答案： C B D A

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