Read the article and select the best answer. Article: A food additive is any substance that is added to food. Many people are put off by the idea of "chemicals in food." The truth is that all food is made up of chemicals. Natural substances like milk, as well as man-made ones like drinks on sale in the market, can be described by chemical formulas. Some chemical substances are indeed harmful, but a person who refused to consume any chemicals would find nothing to eat. The things we eat can be divided into natural and man-made substances. Some people feel that only natural foods are healthy and that all man-made ingredients are to be avoided. But many natural chemicals, found in plants and animals, are harmful when eaten, and some laboratory-made substances increase the nutritional value of food. Other chemicals have natural and man-made forms that are exactly alike: vitamin C is vitamin C, whether it comes from a test tube or from an orange. Like "chemical", "man-made" doesn't necessarily mean "not fit to eat". Food additives are used for many reasons. We add sugar and salt and other things to foods we prepare at home to make them taste better. Food producers have developed a range of additives that stabilize, thicken, harden, keep wet, keep firm, or improve the appearance of their products. Additives can make food more convenient or nutritious, give it a longer shelf life, and make it more attractive to the consumer, thus increasing the sales and profits of the producers. Food additives are presently the centre of a storm of serious argument. Food producers have been known to use additives that have not been proved safe; some substances in common use have been proved unsafe and have been taken off the market. Many people feel there's a risk of eating food to which anything has been added. But food additives are now regulated by the FDA of the federal government, and new additives will go through strict testing before they can be placed on the market. For most people, the chances of developing serious side effects from the long-term use of presently approved... Question: According to the writer, the food additive is _ . Options: A: worrying B: acceptable C: poisonous D: avoidable
B

Read the article and select the best answer. Article: If your mother wants to tell you something , she uses words . Birds can not talk as we do . But some birds can make sounds to warn their young of danger . They have their own ways to make the young birds do certain thing . The jackdaw is a kind of blackbirds that lives in Europe . Jackdaws live together in flocks. Yong jackdaws do not know their enemies . When an older jackdaw sees a dog , it makes a loud tattling sound. The young birds know this sound means an enemy is nearby. The sounds warns them to know their enemy . If a young jackdaw is in a dangerous place, a jackdaw parent flies over him from behind .The parent bird flies low over the young birds back, the parents' tail feathers move quickly from side to side, It is trying to say , " Follow me ." At the same time , the parent calls out , " Key-aw ,Key-aw ." The parent means , " Fly home with me ." The young bird then follows the older one home . Young jackdaws do not have to learn what certain sounds mean. They know the meaning of these sounds from the time they hatch (,). Question: Which of the following does this story lead you to believe ? Options: A: All animal parents can talk to their young. B: Dogs are the most dangerous enemies for jackdaws. C: Young jackdaws know the meaning of their parents sound when they grow older. D: Some birds can give certain information to one another.
D

Read the article and select the best answer. Article: Three men were travelling across the desert when their car broke down. There were no other traffics, so their only hope was to walk. Before they set off, they looked around in the car for useful things to take with them. One of the men took a bottle of whisky. Another took an umbrella. The third unscrewed a door from the car and carried that. After they had been walking for almost a day, they came across a camel caravan travelling towards them. "Let's try to join the caravan," one of the men said. "It's going the wrong way but we'll be safer than if we keep on alone across the desert." The other s agreed, so they asked the leader of the caravan for permission to join it. "You can join the caravan only if you answer three questions," he said. He pointed to the first man's bottle. "What is that and why are you carrying it?" he asked. "It's a bottle of whisky. I decided to carry it with me so that if I feel miserable and want to give up, I can get drunk, cheer myself up and then keep on walking." "Very sensible," the leader of the caravan said. Then he pointed to the next man and his umbrella. "It hasn't rained in the desert for many years," he said. "Why are you carrying an umbrella?" "I don't want to get heat exhaustion," he replied. "The umbrella will give me shade from the sun." "Very sensible," the leader of the caravan said. He pointed to the third man and his car door. "And why are you carrying a car door?" he asked him. "I thought that if I got too hot I could open the window and let some air in," he explained. Question: Each of the men took _ . Options: A: something to eat B: something to drink C: something to keep the rain off D: something to use on their walk
D

Read the article and select the best answer. Article: Edward Wilson The Future of Life, . Edward Wilson is America's, if not the world's, leading naturalist. In The Future of Life, he takes us on a tour of the world's natural resources . How are they used? What has been lost? What remains and is it able to continue with the present speed of use? Wilson also points out the need to understand fully the biodiversity of our earth. Wilson begins with an open letter to the pioneer in environment protection, Henry David Thoreau. He compares today's Walden Pond with that of Thoreau's day. Wilson will use such comparisons for the rest of the book. The problem is clear: man has done great damage to his home over the years. Van the earth, with human help, be made to return to biodiversity levels that will be able to support us in the future? Biodiversity, Wilson argues, is the key to settling many problems the earth faces today. Even our agricultural crops can gain advantages from it. A mere hundred species are the basis of our food supply, of which but twenty carry the load. Wilson suggests changing this situation by looking into ten thousand species that could be made use of, which will be a way to reduce the clearing of the natural homes of plants and animals to enlarge farming areas. At the end of the book, Wilson discusses the importance of human values in considering the environment. If you are to continue to live on the earth, you may well read and act on the ideas in this book. Question: We can infer that the text is _ Options: A: a description of natural resources B: a research report C: a book review D: an introduction to a scientist.
C