题目内容：
根据以下材料，回答题AsWestNileviruscreepstowardCalifornia,anunlikelywarriorcouldprovidethef'n-stlineofdefense:thechicken.Thefamiliarfowlmakeirresistibletargetsformosquitoes.Unlikecrows,chickensdon'tgetsickfromWestNile.Buttheydoproducetelltaleantibodiestothevirus.sointestcoopsscatteredacrossthestate,morethan2000"sentinelchickens"submittofrequentbloodtests.Whenantibodiesdoturnup,Californiahealthofficialswillknowthattheinevitablehasoccurred:theWestNileepidemicwillhavesweptthecountry.
Lastweekalone,morethan100newhumancasesofWestNilewerereported.TheviruswasdetectedasfarwestasColoradoandWyoming,infecting371andkilling16peoplein20statesplustheDistrictofColumbia.ThisyearWestNileappearedearlierinthemosquitoseason--mid-JuneinsteadofAugust-andclaimedyoungervictims;theaverageagedroppedfrom65to54.Federalhealthofficialsarestilltryingtofigureoutwhy,butsaytheymaybefindingmoreWestNilepreciselybecausethey'reonthelookoutforit.AsDr.JulieGerberding,thenewdirectoroftheCentersforDiseaseControl(CDC),recentlytoldreporters,"We'renotincrisismode."
WhenWestNilehitNewYorkCityin1999,theCDCrealizeditwasavictimofitsownsuc-cess.Becausehealthofficialshadconqueredmostmosquito-bornediseasesdecadesago,manystatesabolishedtheirmosquito-controlprograms.TheFedsrushedinwithfunds-some$50millionsince1999,plus$31millionmorethisyearalone-totraininsectresearchers,setupstatetestinglabsandkillofftheannoyinginsects.TheCDCestablishedanewcomputermonitoringsystemandheldstrategysessionswithstateofficials.
someepidemiologistsquestionthefocusandthemillionslavishedonavirusthat'skilledfewerthan20."There'sanepidemicingunviolencethat'stakingmorelivesthanWestNilevirus,"saysDr.WilliamSteinmann,directoroftheTulanceCenterforClinicalEffectivenessandPrevention.ButtheFedssaytheireffortshavekeptWestNilefromdoingfarmoredamage."We'rebasicallybuildingtheinfrastructuretodealwiththisoverthenext50years,"saysDr.LylePeterson,aCDCep-idemiologist."Thisisheretostay."
sofar,therearenoremediesforWestNile.Officialseventuallyexpectthevirustosettleintoaquietpatternofmildinfectionswithoccasionaloutbreaks.todobattleathome,theCDCrecommendseliminatingstandingwaterandusinginsectspraywithDEET-simpleprecautions,butthebestdefenseagainstaninvaderthatshowsnosignsofgoingaway.
InCaliforniascientistsusechickento A．sweepawaytheWestNileepidemic.
B．produceantibodiestoWestNilevirus.
C．fightagainstthespreadofWestNilevirus.
D．monitorthepresenceoftheWestNilevirus.
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