C
Holding a cell phone against your ear or storing it in your pocket may be dangerous to your health. This explains a warning that cell phone manufacturers include in the small print that is often ignored when a new phone is purchased. Apple, for example, doesn’t want iPhones to e closer to you than 1.5 centimeters; Research In Motion, BlackBerry’s manufacturer, remends 2.5 centimeters.
If health issues arise from cell phone use, the possible effects are huge. Voice calls - Americans chat on cell phones 2.26 trillion(万亿)minutes annually - earn $109 billion for the wireless carriers.
Devra Davis, an expert who has worked for the University of Pittsburgh, has published a book about cell phone radiation, “Disconnect.” The book surveys scientific research and concludes the question is not settled.
Brain cancer is a concern that Ms. Davis examines. Over all, there has not been an increase in its incidence since cell phones arrived. But the average masks an increase in brain cancer in the 20-to-29 age group and a drop for the older population.
“Most cancers have multiple causes,” she says, but she points to laboratory research that suggests low-energy radiation could damage cells that could possibly lead to cancer.
Children are more vulnerable to radiation than adults, Ms. Davis and other scientists point out. Radiation that penetrates only five centimeters into the brain of an adult will reach much deeper into the brains of children because their skulls are thinner and their brains contain more absorptive fluid（易吸收的液体）. No studies have yet been pleted on cell phone radiation and children, she says.
Henry Lai, a research professor in the bioengineering department at the University of Washington, began laboratory radiation studies in 1980 and found that rats exposed to radiation had damaged DNA in their brains.
Ms. Davis remends using wired headsets or the phone’s speaker. Children should text rather than call, she said, and pregnant women should keep phones away from the abdomen（腹部）.
【小题1】Why is the warning in the small print?A．They think people will not care about it.B．There is not enough space for the warning. C．They don’t want the users to pay attention to it.D．The warning is not important at all.【小题2】 What does the underlined word in sixth paragraph probably mean?A．acceptable B．valuableC．accessible D．easily affected【小题3】What can we conclude from the last paragraph?A．Pregnant women should keep cell phones away.B．People should use cell phones in the correct way.C．If you are a child, you’d better text than make phone calls.D．When you use a cell phone, use a wired headset or the phone’s speaker.【小题4】 What does the passage mainly talk about?A．Be careful when using cell phones.B．Don’t hold your cell phone against your ear.C．Rats exposed to radiation have damaged DNA in their brains.D．Low-energy radiation could damage cells that could lead to cancer.C
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(答案→)C
解析：本文主要讲述的就是手机的放射性对人的影响，告诫我们使用手机要当心。
【小题1】C 细节题。根据文章第一段2,3行This explains a warning that cell phone manufacturers include in the small print that is often ignored when a new phone is purchased.可知他们不想使用者了解它的危害。故C正确。
【小题2】D 推理题。根据Children are more vulnerable to radiation than adults, Ms. Davis and other scientists point out.说明孩子对于放射性的影响更为敏感，更容易受到影响。故D项正确。
【小题3】B 推理题。根据文章最后一段Ms. Davis remends using wired headsets or the phone’s speaker. Children should text rather than call, she said, and pregnant women should keep phones away from the abdomen（腹部）.可知我们要使用耳机之类的工具，如果可能尽量使用短信，来减少对手机的使用。故B正确。
【小题4】A 主旨大意题。本文主要讲述的就是手机的放射性对人的影响，告诫我们使用手机要当心。故A正确。