100分求一道简单英语阅读理解题目,要求答案注明理由41.Today,asineveryotherdayoftheyear,morethan3000U.S.adolescents（青年人）willsmoketheirfirstcigaretteontheirwaytobecomingregularsmokersasadults.Durin

　　100分求一道简单英语阅读理解题目,要求答案注明理由

　　41.

　　Today,asineveryotherdayoftheyear,morethan3000U.S.adolescents（青年人）willsmoketheirfirstcigaretteontheirwaytobecomingregularsmokersasadults.Duringtheirlifetime,itcanbeexpectedthatofthese3000about23willbemurdered,30willdieintrafficaccidents,andnearly750willbekilledbyasmoking-relateddisease.Thenumberofdeathsattributedtocigarettesmokingoutweighsallotherfactors,whethervoluntaryorinvoluntary,asacauseofdeath.

　　Sincethelate1970s,whendailysmokingamonghighschoolseniorsreached30percents,smokingratesamongyouthhavedeclined.Whilethedeclineisimpressive（印象深刻的）,severalimportantissuesmustberaised.

　　First,inthepastseveralyears,smokingratesamongyouthhavedeclinedverylittle.Second,inthelate1970s,smokingamongmalehighschoolseniorsexceededthatamongfemalebynearly10percent.Thestatisticisreversing.Third,severalrecentstudieshaveindicatehighschooldropoutshaveexcessivelyhighsmokingrates,asmuchas75percent.

　　Finally,thoughsignificantdeclinesinadolescentsmokinghaveoccurredinthepastdecade,nodefinitereasonsforthedeclineexist.Withinthiscontext,theNationalCancerInstitute(NCI)beganitscurrentefforttodeterminethemosteffectivemeasurestoreducesmokinglevelsamongyouth.

　　Accordingtotheauthor,thedeathsamongyoutharemainlycausedby_____.

　　单选题

　　A.trafficaccidents

　　B.smoking-relateddisease

　　C.murder

　　D.allofthese

　　Everydaythereareover_____highschoolstudentswhowillbecomeregularsmoker.

　　单选题

　　A.75

　　B.23

　　C.30

　　D.3000

　　By"dropout"theauthormeans______.

　　单选题

　　A.studentswhofailedtheexamination

　　B.studentswholeftschool

　　C.studentswholosttheirway

　　D.studentswhoweredrivenoutofschool

　　Thereasonfordecliningadolescentsmokingisthat________.

　　单选题

　　A.NCIhastakeneffectivemeasures

　　B.smokingispreventedamonghighschoolseniors

　　C.therearemanysmokerswhohavediedofcancer

　　D.none