题目

阅读下列短文，从每题所给的A、B、C和D四个选项中，选出最佳选项。 When Gitanjali Rao was 11, she invented equipment that quickly detects(检测) lead in water. She became the youngest ever winner of the Discovery Education 3M Young Scientist Challenge. In 2016, the news was full of stories about dangerous drinking water in Flint, Michigan. The water had too much lead in it. Lead is a metal that can cause health problems when people eat or drink it. There was home test equipment that could detect lead in water. But these tests didn't work very well. They took too long and often gave wrong results. Gitanjali wondered if she could create a test that was quick, easy, and right. One day, Gitanjali read a news story about using carbon nanotubes(纳米管) to test for poison in the air. The nanotubes were coated with a chemical that stuck to the poison. When the poison stuck, it changed the way electricity flowed through the tubes. Scientists could measure the electric flow to see how much poison was in the air. Gitanjali wondered if she could use the same way to detect lead in water. She e-mailed a chemistry teacher at her local school. They didn't have a fancy lab, but it was good enough for Gitanjali to test whether her detector could sense lead at all. They started by testing clean water. The electricity meter jumped all over the place. Gitanjali learned how to adjust it. Next they added tiny spoons of lead. After many, many tries—her detector worked. Then Gitanjali made a phone app so users could use the results instantly on their phones. She entered her idea in a big national competition. When she was picked for the semi-finals, she was assigned an advisor to help her work on her equipment. And—she won! Gitanjali's next goal is to sell her equipment in stores and make versions that test for different kinds of pollution. She is also very interested in genetics(遗传学). （1） What caused Gitanjali to be the winner of the Discovery Education 3M Young Scientist Challenge? A . Her phone app of detecting lead in the air. B . Her new discovery of lead in water. C . Her equipment of detecting lead in water. D . Her new ideas of finding lead in the air. （2） Where did Gitanjali get the inspiration of her invention? A . From the 2016 news. B . From the news story she read. C . From a chemistry teacher. D . From a chemistry lesson. （3） What does the underlined word "it" in Paragraph 5 refer to? A . The place. B . Her detector. C . The quantity of lead in water. D . The electricity meter. （4） Which words can be used to describe Gitanjali? A . Determined and creative. B . Hard-working and outgoing. C . Confident and devoted. D . Energetic and sincere. 答案： C B D A

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