题目内容：
请阅读Passage2，完成第小题。
Globalwarmingmayornotbethegreatenvironmentalcrisisofthe21stcentury,butregardlessofwhetheritisornot,wewon'tdomuchaboutit.Wewillargueoveritandmayeven,asanation,makesomefairlysolemn-soundingcommitmentstoavoidit.Butthemoredramaticandmeaningfulthesecommitmentsseem,thelesslikelytheyaretobeobserved.
A1Gorecallsglobalwarmingan"inconvenienttruth",asifmerelyrecognizingitcouldputusonapathtoasolution.Buttherealtruthisthatwedon'tknowenoughtobelieveglobalwanning,and--withoutmajortechnologicalbreakthroughs--wecan'tdomuchaboutit.
From2003to2050,theworld'spopulationisprojectedtogrowfrom6.4billionto9.1billion,a42%increase.Ifenergyuseperpersonandtechnologyremainthesame,totalenergyuseandgreenhousegasemissions(mainly,CO2)willbe42%higherin2050.Butthat'stoolow,becausesocietiesthatgrowricherusemoreenergy.Weneedeconomicgrowthunlesswecondemntheworld'spoortotheirpresentpovertyandfreezeeveryoneelse'slivingstandards.Withmodestgrowth,energyuseandgreenhouseemissionswillmorethandoubleby2050.
Nogovernmentwilladoptrigidrestrictionsoneconomicgrowthandpersonalfreedom(limitsonelectricityusage,drivingandtravel)thatmightcutbackglobalwarming.Still,politicianswanttoshowthey're"doingsomething".ConsidertheKyotoProtocol.Itallowedcountriesthatjoinedtopunishthosethatdidn't.Butithasn'treducedCO2emissions(upabout25%since1990),andmanysignatoriesdidn'tadopttoughenoughpoliciestohittheir2008-2012targets.
Thepracticalconclusionisthatifglobalwarmingisapotentialdisaster,theonlysolutionisnewtechnology.Onlyanaggressiveresearchanddevelopmentprogrammightfindwaysofbreakingourdependenceonfossilfuelsordealingwithit.
Thetroublewiththeglobalwarmingdebateisthatithasbecomeamoralproblemwhenit'sreallyanengineeringone.Theinconvenienttruthisthatifwedon'tsolvetheengineeringproblem,we'rehelpless.
Whatissaidaboutglobalwarminginthefirstparagraph? A．Itmaynotproveanenvironmentalcrisisatall.
B．Itisanissuerequiringworldwidecommitments.
C．Seriousstepshavebeentakentoavoidorstopit.
D．Verylittlewillbedonetobringitundercontrol.
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