问题 阅读理解
A new study has found no evidence that sunscreen, commonly used to reduce the risk of skin caner, actually increases the risk.
Researchers from the University of Yale based their findings on a review of 18 earlier studies that looked at the association between sunscreen use and melanomas (黑素瘤). They said that they found flaws in studies that had reported associations between sunscreen use and higher risk of melanoma.
Most health experts believe that by protecting the skin from the harmful effects of the sun, sunscreen helps prevent skin cancer, which is increasing in incidence (发生率) faster than any other cancer in the United States.
But questions have been raised about sunscreen and whether it may have the opposite effect, perhaps by allowing people to remain exposed to the sun longer without burning.
The researchers said that among the problems with some earlier studies is that they often failed to take into account that those people most at risk for skin cancer—people with fair skin and freckles (雀斑), for example—are more likely to use sunscreen. As a result, it may appear that sunscreen users get cancer more often.
The studies, which generally relied on volunteers to recall their sunscreen use, were also unable to prove how well the products had been applied, said the new study.
小题1:The underlined word “flaws” in the 2nd paragraph most probably means           .
      
A.evidencesB.factsC.faultsD.failures
小题2:People with fair skin and freckles           .
      
A.seldom use sunscreenB.are more in danger of skin cancer
C.can be free from the harm of the sunD.often expose themselves to the sun
小题3:We can learn from the passage that          .
      
A.sunscreen users get skin cancer more often
B.the volunteers have proved the effect of sunscreen
C.the new study was based on the experiences of volunteers
D.the number of skin cancer patients is increasing in America
小题4:Which of the following can be the best title for this passage?
      
A.Sunscreen to Prevent Skin Cancer
B.Sunscreen to Increase Skin Cancer
C.Skin Cancer Caused by Sunscreen
D.Skin Cancer Caused by Freckles
答案

小题1:C

小题1:B

小题1:D

小题1:A

单项选择题

阅渎下面短文,回答下 * * 道题。
如果认识到我们对于生活在我们四周的许多生物的相互关系还有很多不了解的,那么,关于物种或变种的起源问题,我们即使有很多地方不能解释,也就不足为奇了。为什么某种生物的分布广泛而繁多,而它的邻种却分布得狭小而稀少呢谁能解释这个问题呢然而这些关系,实在是非常重要,因为我相信,这是决定地球上每一生物的现在和将来的命运,以及变异的趋向的。对于生活在过去的地质时代的无数生物的相互关系,我们所知道的就更少了。虽然许多事实现在还是不清楚,而且在未来长期内也还弄不清楚,但是我们经过了精细的研究和冷静的判断,可以毫不怀疑地断言创造论的错误。创造论这一观点,虽为近代许多博物学家所信奉,我自己以前也曾信奉过,但是事实上决不能成立。我深信生物的种不是不变的;所谓同属的种,都是其他大概已经灭亡的种所传下来的直系后代,而现在认为同种的各项变种,都是这同种的后代。我又确信自然选择作用,它虽然不是物种变异的唯一条件,也该是最重要的条件。
(选摘自《物种起源导言》)

对选文第一句话理解完全正确的一项是:

A.我们对于生活在我们四周的许多生物的相互关系还有很多不了解的。

B.关于物种或变种的起源我们还有很多地方不能解释。

C.关于物种或变种的起源我们还有很多地方不能解释是很自然的事情。

D.我们对于生活在我们四周的许多生物的相互关系尚且有很多不了解的,那么,关于物种或变种的起源我们还有很多地方不能解释就是很自然的事情了。

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