Question

American researchers say drinking tea may help strengthen the body's defense system against infection（感染）．Doctors at Brigham and Women's Hospital in Boston,Massachusetts,did the study．The team studied a chemical found in black,green,oolong and pekoe tea．This chemical is an amino acid（氨基酸）called L-theanine．The scientists say it may increase the strength of gamma delta T cells．That's the letter T,not the drink．Gamma delta T cells are part of the body's defenses． 　　First,the researchers mixed some of these cells with antigens（抗原）found in the amino acid．Antigens help the body react to infection．Then the scienists added some bacteria（细菌）．Within twenty-four hours,the cells produced a lot of interferon,a substance that fights infection．Cells not mixed with the antigens did not produce interferon． 　　In the second part of the study,eleven people drank fiveto six cups of black tea everyday．Ten other people drank the same amount of instant coffee．That is dried coffee mixed with hot water． 　　Two weeks later,and again two weeks after that,the researchers tested the blood of all twenty-one people．They alsolooked at what happened when they added bacteria to the blood cells．They found that the tea drinkers produced five times more interferon after they started drinking tea．The coffee drinkers did not produce interferon． 　　Doctor Jack Bukowski led the study．He says the antigens added to the gamma delta T cells were responsible for the increased reaction to the bacteria．He says the study also showed that the cells were able to remember the bacteria and fight them again the next time． 　　Earlier research already has found that tea can help prevent heart disease and cancer．Doctor Bukowski says the new study must be repeated with more people．If the findings prove to be true,he says,then tea drinking might also help protect against bacterial infections．He says,the amino acid L-theanine could be removed from tea and used as a drug to strengthen the body's defenses． (1) We may know from the text that________can be foundin different kinds of tea． [　　] A． gamma delta T cells B． L-theanine C． interferon D． bacteria (2) Tea may help strengthen the body's defense systembecause it helps ________ [　　] A． the body to produce more interferon B． the body to produce more gamma delta T cells C． to add some bacteria to the blood cells D． to mix antigens with some of the cells in the body (3) According to Dr Bukowski,________ [　　] A． the findings of the study have already proved to be true B． he has taken some amino acid L-theanine from tea and made a drug with it C． further study is needed to prove the findings true D． he is not sure whether tea can help prevent heart disease and cancer (4) What would be the best title for this text? [　　] A． Tea Is Better Than Coffee B． Tea May Help Fight Infection C． Tea Can Help Prevent Cancer D． Our Body Needs Tea

Answer 1

答案：1．B;2．A;3．C;4．B;
解析：

(1)	从第一段中可以选出正确答案
(2)	从第二段Within twenty-four hours，the cells produced a lot of interferon，a substance that fights infection中可以判断。
(3)	从第六段中可以看出，尽管Earlier research already has found that tea can help prevent heart disease and cancer，但是Doctor Bukowski says the new study must be repeated with more people，所以答案为C．
(4)	通读全文，不难看出“茶有助于抗感染”是文章的主题。