Cell phones：Is there a cancer link？
Could your cell phone give you cancer？Whether it could or not，some people are worrying about the possibility that phones，power lines and Wi﹣Fi could be responsible for a range of illnesses，from rashes to brain tumors．
Some say there is evidence to support the growing anxieties．David Carpenter，a professor of environmental health sciences at the university at Albany，in New York，thinks there's a greater than 95percent chance that power lines can cause childhood leukemia （白血病）．Also there's a greater than 90percent chance that cell phones can cause brain tumors．"It's apparent now that there's a real risk，"said Carpenter．
But others believe these concerns are not justified．Dr Martha Linet，head of radiation epidemiology （流行病学） at the US National Cancer Institute，has looked at the same research as Carpenter but has reached a different conclusion．"I don't support warning labels for cell phones，"said Linet．"We don't have the evidence that there's much danger．"
Studies so far suggest a weak connection between EMFs （电磁场） and illness﹣so weak that it might not exist at all．A multinational investigation of cell phones and brain cancer，in 13countries outside the US，has been underway for several years．It's funded in part by the European Union，in part by a cell phone industry group．The final report should come out later this year，but data so far don't suggest a strong link between cell phone use and cancer risk．
42．From the passage we can learn that some people are worried because ．
A．they have evidence that the use of cell phones can lead to cancer
B．they feel surprised and alarmed about cell phone use
C．some experts have given a warning
D．cell phones are responsible for brain tumors
43．By saying"I don't support warning labels for cell phones，"Dr Martha Linet has the idea that ．
A．the worrying is unnecessary
B．cancer﹣warning labels should be on cell phones
C．there is a link between cell phones and cancer
D．cell phones have nothing to do with cancer
44．Which of the following best describes the attitude of the author towards the debate？
A．Optimistic．
B．Objective．
C．Opposite．
D．Casual．
45．The underlined word"justified"in Paragraph 3is closest in meaning to ．
A．explained
B．confirmed （证实、确认）
C．classified
D．restricted （限制）