题目内容：
根据以下材料，回答题Text 2
Thethreatofdiseasessuchasinfluerlzaortuberculosisre-emerginginvirulentformhasbeenacommonthemeinrecentyears.Thatthreatisnotlimitedtohumandiseases.Ourfoodplantsgetsicktoo,andjustashumandiseasesevolvetoevadeantibiotics,
sothediseasesthatstrikeourcropsevolvetosidesteptheresistancegeneswehavebredintothem.Forthevastmajorityofthecaloriestheworldeats,thekeycropisgrain.
Aruinouswheatdiseasewehavenothadtoworryaboutsincethe1950sismakingacome-back,andunlessweareverylucky,wewillnothavesufficientdefencestoprotectcropsevery-wherein
theworldagainstitintime.Thatstemrustwouldevolveandreturntoplagueuswasin-evitable,butourlackofpreparationtowarditoffwasnot.
Researchintostemrustwasboundtotailoffoncethediseaseseemedbeaten,buttheworldletdownitsguardtoofar,forideologicalreasons.Inthe1980sgovernmentsofindustrializedcoun-tries,especiallytheUKandUS,startedtolosepatiencewiththe"multilateral"agenciesthatengi-neeredmuchoftheglobalprogressinagricultureaftertheSecondWorldWar.Eachgovernment
wantedtheagenciestodanceonlytoitstune.ThisincludedtheConsultativeGroupforInternation-alAgriculturalResearch,theglobalnetworkoflabsthatcreatedthe"GreenRevolution".
TheCGIARremainstheleading,sometimesonlysourceofagriculturalresearchdevotedtoglobalgoodratherthanprivateprofit.
"Multilateral"fundingmeanttheselabsreceivedincomefromrichdonorswithnostringsatta-ched.Researchersatthelabswereabletospendthemoneythewaytheythoughtbest--includingtheunglamoroustaskofmakingsurethatcrops'diseaseresistancekeptpacewiththediseases.However,formorethantwodecades,donorshavebeencuttingthisfundinginfavourofonly
fi-nancingprojectsalliedtotheirowninterests.Aswheatstemrustre-emergedin1999,themainCGIARwheatlabwasenteringamajorfundingcrisis,andendedupsackingaquarterofitsscien-tists.Ithastakenuntilnowtobegenoughmoneytofightthedisease.
Therearenowsignsthatdonorsmaybemovingbacktomoreopen-endedfunding,whichistobeencouraged.Theyshouldalsoincreasetheirderisoryfundingforthisvitalresearch:stemrustispoisedtoteachusthedangersofcomplacency.
Theworldpopulationispredictedtorisebyanother3billionby2050,yetincreasesinfoodproductionhavestagnated,technologicalfixesarespent,andglobalwarming--andthereturnofdiseaseslikestemrust--looklikelytotakebackmanyofthegainswehavemade.Foodsecurityaffectspoliticalsecurity,andoneofthefirstregionstosufferfromstemrustwillbethevolatileMiddleEast,includingIraq.
Agriculturalresearchforthepublicgoodistheonlywaytoprovidethatsecurity.Itiscertainlycheaperthanbuildingarmies.
Thehumanandcropdiseasesonceundercontrolhavecomebackagainbecause A．antibioticsdonotworkanymore.
B．humandiseasesspreadtoplants.
C．thereisgeneticresistanceinthem.
D．humaninterventionsnolongerwork.
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