题目内容：
根据以下材料，回答题 Diabetes(糖尿病)andEyeDamage
Over2millionCanadianshavediabetes．ItistheleadingcauseofblindnessinNorthAmericansunder65yearsofage．Diabetesisaconditionwherethebodyeithercannotproduceenoughinsulin(胰岛素)orcannotrespondproperlytoinsulin．Insulinisimportantbecauseitmovesglucose(葡萄糖),asimplesugar,intothebody'scellsfromtheblood．Thefoodpeopleeatprovidesthebodywithglucose,whichisusedbythecellsasasourceofenergy．Ifinsulinisn'tavailableordoesn'tworkcorrectlytomoveglucosefromthebloodintothecells,glucosewillstayintheblood,leadingtohighbloodsugarlevels.
Highbloodsugarlevelsdamagethebloodvessels,includingthetinybloodvesselsintheeye．Thisleadstoaneyediseaseknownasdiabeticretinopathy(糖尿病型视网膜病)Theretina(视网膜)isanareaatthebackoftheeyethatchangeslightintonervesignals．Withdiabeticretinopathy,somebloodvesselsintheretinaarelost,andsomeoftheotherbloodvesselsbeginto"leak"blood．Thiscausestheretinatoswellandgraduallycutsoffitssupplyofoxygenandnutrients(滋养物)．Eventually,theretinastartstogrownewbloodvesselstoreplacethedamagedones．Unfortunately,thesenewvesselsarenotasstrongastheoldones.
Theyaremorelikelytobreak,causingbleedingintheeye.
Atfirst,peoplewithdiabeticretinopathywillnotnoticeanysymptoms．Asthediseasegetsworse,theymaynoticeblurred(模糊的)vision,blackspotsorflashinglights．Astimegoeson,itcanprogresstoblindness.
Everyonewithdiabetesisatriskofdiabeticretinopathy,andtheriskincreasesthelongeryou'vehaddiabetes.
Fortunately,youcanreduceyourriskifyoudonothavediabetes,butthinkyoumaybeatriskofthiscondition．Visityourdoctortobescreenedfordiabetes．Ifyoudohavediabetes,havefrequenteyecheck-ups.
Makesurethatyoumonitoryourbloodsugarfrequentlyanduseyourmedicationsasrecommendedbyyourdoctor．Thereisevidencetoshowthatkeepingyourbloodsugarundertightcontrolcanslowdowneyedamage．Ifyouhavehighbloodpressure,followyourrecommendeddietandmedicationstokeepitundercontrol．Ifyouarenotsurewhetheryouhavehighbloodpressure,orwhetheryourbloodpressureisundercontrol,discussthiswithyourdoctor.
Glucosecannotbeturnedintoenergyinthebody__________. A．withoutdiabetes
B．withoutsugar
C．withoutinsulin
D．withoutfood
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