阅读理解阅读理解

阅读下列短文，然后从各题所给的四个选项(A、B、C和D)中，选出最佳选项。

Whydoescreamgobadfasterthanbutter?Someresearchersthinktheyhavetheanswer,anditcomesdowntothestructure(结构)ofthefood,notitschemicalcomposition(成分)afindingthatcouldhelpbreakawayfromsomechemicals.Creamandbuttercontainprettymuchthesamethings,sowhycreamshouldgobadmuchfasterhasbeenaproblem.Botharesmallglobules(小球)ofoneliquidspreadthroughoutanother.Thedifferenceliesinwhat'sintheglobulesandwhat'sinthesurroundingliquid,saysBrocklehurst,wholedtheresearch.Incream,fattyglobulesdriftaboutinaseaofwater.Inbutter,globulesofawateryroadarelockedawayinaseaoffat.Thebacteria(细菌)whichmakethefoodgobadprefertoliveinthewateryareasofthemixture.“Thismeansthatincream,thebacteriaarefreetogrowthroughoutthemixture,”hesays.Wheninbutter,thebacteriaarelockedawayinlockedplacesburieddeepintheseaoffat.Trappedinthisway,thosecoloniescannotspreadandrapidlyrunout.Theyalsoslowlypoisonthemselveswiththeirwasteproducts.“Inbutter,yougetaself-limitingsystemwhichstopsthebacteriagrowing,”saysBrocklehurst.Theresearchersarealreadyworkingwithfoodcompanieseagertoseeiftheirproductscanbemadetostandbacterialattackthroughchangesofthefoods'structure.Brocklehurstbelievesitwillbepossibletomakesomethingusedinsaladcreamforinstance,morelikethatinbutter.Thekeywillbetodothiswhilekeepingthesaladcreamliquidandnotturningitintoasolidstate.

1．Accordingtotheresearchers,creamgoesbadfasterthanbutterbecausebacteria________.

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A．arestrongerincream

B．increasetheirnumbermoreeasilyincreamthaninbutter

C．liveonlessfatincreamthaninbutter

D．producelesswasteincreamthaninbutter

2．AccordingtoBrocklehurst,wecankeepcreamfreshby________.

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A．removingitsfatB．killingthebacteriaC．reducingitswaterD．changingitsstructure3．Theunderlinedword“colonies”refersto________.

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A．tinyglobulesB．wateryregionsC．bacteriasocietyD．littledepartments4．Commerc