2025年托福《阅读》真题回忆版

2025年托福《阅读》真题回忆版

Passage1

TheRoleofPermafrostinGlobalCarbonCycling

Permafrost,definedasground(soilorrockandincludediceororganicmaterial)thatremainsatorbelow0°Cforatleasttwoconsecutiveyears,playsacriticalroleintheglobalcarboncycle.Itisfoundinhigh-latituderegionssuchastheArctic,Antarctica,andhigh-altitudeareas.Formillennia,permafrosthasactedasavastcarbonsink,trappingorganicmatterandpreventingitsdecomposition.However,withtheadventofanthropogenicclimatechange,thisstablestoragesystemisunderthreat.Asglobaltemperaturesrise,thethawingofpermafrostreleasesstoredcarbonintheformofcarbondioxide(C)andmethane(C),creatingapotentialfeedbackloopthatcouldacceleratewarmingfurther.

Theamountoforganiccarbonstoredinpermafrostisstaggering.Estimatessuggestthatnorthernpermafrostregionscontainapproximately1,400to1,600gigatonsoforganiccarbon,whichisroughlytwicetheamountcurrentlypresentintheEarth'satmosphere.Thisorganicmatterconsistsoftheremainsofplantsandanimalsthataccumulatedoverthousandsofyearsduringthelasticeage.Becausethegroundremainedfrozen,microbialactivity—whichbreaksdownorganicmatter—washalted.Consequently,thiscarbonremainedsequestered.Therateofmicrobialrespiration,R,infrozensoilisnegligible,butitincreasesexponentiallyastemperaturerises,followingarelationshipoftenmodeledbytemperaturecoefficients,where=·.

Whenpermafrostthaws,theenvironmentchangesdramatically.Thegroundbecomesunstable,leadingtothermokarstlandscapescharacterizedbysinkinggroundandtheformationofnewlakes.Inanaerobic(oxygen-free)environments,suchaswater-saturatedthermokarstlakes,microbesdecomposeorganicmatterthroughmethanogenesis,producingmethane.Methaneisapotentgreenhousegas,withaglobalwarmingpotentialover25timesgreaterthanthatofCovera100-yearperiod.Inaerobic(oxygen-rich)environments,decompositionproducescarbondioxide.Thebalancebetweenthesetwogasesdependslargelyonthedrainageconditionsofthethawedsoil.

Theimplicationsofpermafrostthawextendbeyondgasemissions.Thephysicaldisruptionofthelandscapedamagesinfrastructurebuiltonfrozenground,includingroads,pipelines,andbuildings.Moreover,thereleaseofnutrientspreviouslylockedintheicecanalterlocalecosystems,promotingthegrowthofshrubsandvegetationthatmay,inturn,affectsurfacealbedo(reflectivity).Darkervegetationabsorbsmoresunlightthansnow-coveredtundra,leadingtofurtherlocalwarmingandadditionalpermafrostdegradation—aphenomenonknownas"Arcticgreening."

Scientistsarecurrentlyworkingtorefinemodelstobetterpredicttherateandmagnitudeofpermafrostcarbonrelease.Keyuncertaintiesincludethedepthofthaw,thespecificmicrobialpathwaysactivated,andthepotentialfornewvegetationtooffsetsomeemissionsthroughincreasedCuptake.Whilesomemodelssuggestagradualrelease,othersindicatethepossibilityofabruptthawing,whichcouldreleaselargequantitiesofcarboninashortperiod.Understandingthesedynamicsisessentialforglobalclimatepolicy,asthepermafrostcarbonfeedbackcouldsignificantlyreducetheremainingcarbonbudgettokeepwarmingbelow2°C.

1.Theword"anthropogenic"inthepassageisclosestinmeaningto

A.natural

B.human-caused

C.geological

D.atmospheric

2.Accordingtoparagraph2,whyhasorganiccarbonaccumulatedinpermafrostregions?

A.Becausethecoldtemperaturesslowdowntherateofphotosynthesis.

B.Becausethefrozenstatepreventsmicrobialdecomposition.

C.Becausethehighaltitudelimitstheamountofprecipitation.

D.Becausethesoilcompositionpreventstheformationofmethane.

3.Whichofthesentencesbelowbestexpressestheessentialinformationinthehighlightedsentenceinthepassage?

A.Methaneisastrongergreenhousegasthancarbondioxide,butitisproducedinsmallerquantitiesinwater-saturatedenvironments.

B.Thedecompositionoforganicmatterinoxygen-freeenvironmentsproducesmethane,whichissignificantlymoreeffectiveattrappingheatthancarbondioxide.

C.Carbondioxideisproducedinaerobicenvironments,butmethaneisproducedinanaerobicenvironmentsandislessdangeroustotheatmosphere.

D.Globalwarmingpotentialiscalculatedovera100-yearperiod,duringwhichmethanehasasmallerimpactthancarbondioxide.

4.Theword"magnitude"inthefinalparagraphisclosestinmeaningto

A.location

B.scale

C.cause

D.duration

5.Accordingtoparagraph3,whatdetermineswhetherdecompositionproducesmethaneorcarbondioxide?

A.Theageoftheorganicmatterbeingdecomposed.

B.Thespecifictypeofmicroorganismspresentinthesoil.

C.Whethertheenvironmentisa

D.Thedepthofthepermafrostlayer.

6.Whydoestheauthormention"Arcticgreening"inparagraph4?

A.Toillustrateapositivefeedbackloopthatacceleratespermafrostthaw.

B.Tosuggestthatnewplantgrowthcancompletelyreversetheeffectsofwarming.

C.Todemonstratethatpermafrostregionsarebecomingsuitableforagriculture.

D.Toexplainhownutrientreleasebenefitslocalanimalpopulations.

7.WhichofthefollowingisNOTmentionedinthepassageasaconsequenceofpermafrostthaw?

A.Damagetoinfrastructure.

B.Changesinlocalecosystemvegetation.

C.Increaseinvolcanicactivity.

D.Releaseofgreenhousegases.

8.Lookatthefourletters[A,B,C,D]thatindicatewherethefollowingsentencecouldbeaddedtothepassage.

"Consequently,thiscarbonremainedsequestered."

Wherewouldthesentencebestfit?

A.Estimatessuggestthatnorthernpermafrostregionscontainapproximately1,400to1,600gigatonsoforganiccarbon,whichisroughlytwicetheamountcurrentlypresentintheEarth'satmosphere.[A]

B.Thisorganicmatterconsistsoftheremainsofplantsandanimalsthataccumulatedoverthousandsofyearsduringthelasticeage.[B]

C.Becausethegroundremainedfrozen,microbialactivity—whichbreaksdownorganicmatter—washalted.[C]

D.Therateofmicrobialrespiration,R,infrozensoilisnegligible,butitincreasesexponentiallyastemperaturerises,followingarelationshipoftenmodeledbytemperaturecoefficients...[D]

9.Theword"sequestered"inthepassagerefersto

A.exposed

B.analyzed

C.isolatedandstored

D.destroyed

10.Directions:Anintroductorysentenceforabriefsummaryofthepassageisprovidedbelow.CompletethesummarybyselectingtheTHREEanswerchoicesthatexpressthemostimportantideasinthepassage.Somesentencesdonotbelonginthesummarybecausetheyexpressideasthatarenotpresentedinthepassageorareminorideasinthepassage.

Permafrostthawduetoclimatechangeposessignificantriskstotheglobalclimatesystemthroughthereleaseofstoredcarbon.

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A.Permafrostcontainsavastamountoforganiccarbon,twicethatoftheatmosphere,whichhasbeenpreservedinafrozenstate.

B.Microbialdecompositionofthawedorganicmatterreleasesmethaneandcarbondioxide,potentgreenhousegases.

C.TheformationofthermokarstlakesisprimarilycausedbythemigrationoflargeanimalsintheArctic.

D.Physicalchangestothelandscape,suchasgroundinstabilityandalteredvegetation,canfurtheracceleratewarming.

E.Scientistshavedeterminedthatpermafrostthawwillhappengraduallyandpredictablyoverthenextcentury.

F.Carbondioxideistheonlygasreleasedduringthedecompositionoforganicmatterinpermafrostregions.

Passage2

TheDevelopmentoftheCameraObscurainRenaissanceArt

TheevolutionofartistictechniquesduringtheRenaissancewascloselylinkedtoadvancementsinscienceandtechnology.Oneofthemostsignificant,yetdebated,influencesontheriseofphotorealisticpaintinginthe15thand16thcenturieswastheuseofthecameraobscura.Theterm"cameraobscura"isLatinfor"darkroom."Itisanaturalopticalphenomenonthatoccurswhenanimageofasceneattheothersideofascreen(orawall)isprojectedthroughasmallholeinthatscreenasareversedandinvertedimageonasurfaceoppositetotheopening.Thedevicecanbearoomwithasmallholeinthewalloraportableboxwithalens.

TheprincipleofthecameraobscurawasknowntoancientscholarssuchasMoziinChinaandAristotleinGreece,whoobservedthephenomenonoflightpassingthroughasmallapertureintoadarkenedspace.However,itwasnotuntiltheRenaissancethatthedevicewassystematicallyutilizedasatoolforartists.Bythe16thcentury,lenseswereaddedtotheaperture,sharpeningtheprojectedimageandallowingformoreprecisetracing.Thistechnologicalleapenabledartiststocaptureperspective,proportion,andintricatedetailswithunprecedentedaccuracy.

ArthistorianshavelongspeculatedabouttheextenttowhichmasterslikeJanvanEyck,LeonardodaVinci,andparticularlyJohannesVermeerusedthecameraobscura.DavidHockney,acontemporaryartist,andCharlesFalco,anopticalphysicist,famouslyarguedinthe"Hockney-Falcothesis"thatthesuddenriseofopticalrealisminWesternpaintingaround1420waslargelyduetotheuseofopticalprojections.Theypointedtospecificanomaliesinpaintings,suchasthevanishingpointperspectivethatmatchesopticalratherthanhumanvision,andthecomplexlightingpatternsthatresemblethedepthoffieldfoundinlens-basedimages.

Forexample,Vermeer's"TheMusicLesson"exhibitsadepthoffieldcharacteristicofalens;theforegroundtapestryisblurredwhilethefiguresinthemiddledistancearesharp.Thehumaneyenaturallyadjustsfocusconstantly,perceivingthewholesceneassharp,whereasalenscapturesaspecificplaneoffocus.ThisopticaleffectsuggeststhatVermeermayhavetracedtheprojectedimageoruseditasadirectreferencetomapthecolorsandvaluesofthescene.Furthermore,theextremeprecisionofhighlightsinhispaintings,suchasreflectionsonjewelryorglossysurfaces,isdifficulttoachievewiththenakedeyealone.

However,thetheoryisnotwithoutitscritics.Traditionalarthistoriansarguethatthe"Hockney-Falcothesis"underestimatestheskill,training,andobservationalpowersofRenaissanceartists.Theycontendthatthesemastersachievedrealismthroughrigorousstudyofanatomy,geometry,andnature,aswellasthedevelopmentofmathematicalperspectivesystemsinventedbyFilippoBrunelleschi.Theyarguethatwhileartistsmayhaveusedthecameraobscuraasasupplementarytoolforstudyingcomplexcompositionsorlighting,thefundamentalexecutionwasachievedthroughmanualskillandartisticintuition.

Despitethedebate,thecameraobscuraundoubtedlyleftamarkonthehistoryofart.Itservedasabridgebetweenthemanualandthemechanical,foreshadowingtheinventionofphotographyinthe19thcentury.Thedeviceallowedartiststostepoutsidethestudioandengagemoredirectlywiththevisualworld,pavingthewayforthepleinairmovementsofthe19thcentury.Whetherusedasatracingtooloramechanicalaidforunderstandinglight,thecameraobscurarepresentsafascinatingintersectionofart,physics,andtechnologyduringapivotaleraofculturalhistory.

11.Theword"phenomenon"inparagraph1isclosestinmeaningto

A.occurrence

B.experiment

C.philosophy

D.device

12.Accordingtoparagraph2,whatimprovementdidlensesaddtothecameraobscura?

A.Theyallowedtheimagetobeprojectedincolorratherthanblackandwhite.

B.Theyincreasedthesizeoftheroomneededtohousethedevice.

C.Theymadetheprojectedimagesharperandclearer.

D.Theyenabledthedevicetorecordimagesontophotographicpaper.

13.Whatisthe"Hockney-Falcothesis"mentionedinparagraph3?

A.ThetheorythatRenaissanceartistsinventedthecameraobscura.

B.Theargumentthattheriseofopticalrealismwasprimarilyduetotheuseofopticalaids.

C.ThebeliefthatVermeerwastheonlyartistcapableofpaintingwithoutopticaltools.

D.TheideathatperspectivewasinventedbyancientGreekscholars.

14.Theword"anomalies"inparagraph3isclosestinmeaningto

A.masterpieces

B.colors

C.irregularities

D.styles

15.WhydoestheauthormentionVermeer's"TheMusicLesson"inparagraph4?

A.Todemonstratetheartist'slackofskillinpaintingbackgrounds.

B.Toprovideevidencethatsupportstheuseofopticaldevices.

C.Toillustratethedifferencebetweenoilpaintandwatercolor.

D.Toprovethatthehumaneyeseesbetterthanacameralens.

16.Accordingtoparagraph5,whydosomearthistoriansrejecttheheavyrelianceonthecameraobscura?

A.Theybelievethedocumentsprovingitsuseareforgeries.

B.Theythinkthecameraobscurawasnotinventeduntilthe17thcentury.

C.Theyattributetherealismtotheartists'trainingandstudyofgeometry.

D.Theyarguethatthecameraobscuraproducesonlyupside-downimages.

17.WhichofthefollowingcanbeinferredfromthepassageabouttherelationshipbetweenartandtechnologyintheRenaissance?

A.Artistsweregenerallyresistanttousingscientifictoolsintheirwork.

B.Technologicaladvancementswereseparatefromthedevelopmentofartisticstyle.

C.Theintersectionofscienceandartcontributedtonewmethodsofrepresentation.

D.Thecameraobscurawasconsideredatoolforcheatingratherthanart.

18.Lookatthefourletters[A,B,C,D]thatindicatewherethefollowingsentencecouldbeaddedtothepassage.

"Thistechnologicalleapenabledartiststocaptureperspective,proportion,andintricatedetailswithunprecedentedaccuracy."

Wherewouldthesentencebestfit?

A.Theterm"cameraobscura"isLatinfor"darkroom."[A]

B.Itisanaturalopticalphenomenonthatoccurswhenanimageofasceneattheothersideofascreen(orawall)isprojectedthroughasmallholeinthatscreenasareversedandinvertedimageonasurfaceoppositetotheopening.[B]

C.Bythe16thcentury,lenseswereaddedtotheaperture,sharpeningtheprojectedimageandallowingformoreprecisetracing.[C]

D.Thedevicecanbearoomwithasmallholeinthewalloraportableboxwithalens.[D]

19.Theword"pleinair"inthefinalparagraphrefersto

A.paintingoutdoors

B.paintinginadarkroom

C.paintingwithacamera

D.paintingreligiousscenes

20.Directions:Anintroductorysentenceforabriefsummaryofthepassageisprovidedbelow.CompletethesummarybyselectingtheTHREEanswerchoicesthatexpressthemostimportantideasinthepassage.Somesentencesdonotbelonginthesummarybecausetheyexpressideasthatarenotpresentedinthepassageorareminorideasinthepassage.

ThecameraobscurawasanimportantdevicethatinfluencedartistictechniquesduringtheRenaissance.

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A.Thedeviceworksbyprojectinganimagethroughasmallholeorlensintoadarkenedspace.

B.Somescholarsarguethattheopticalrealismofthe15thand16thcenturieswasachievedthroughtheuseofthisdevice.

C.CriticsoftheopticaltheoryemphasizethehighlevelofskillandgeometricknowledgepossessedbyRenaissanceartists.

D.Thecameraobscurawaseventuallyreplacedbytheinventionofthedigitalcamerainthe20thcentury.

E.AllRenaissanceartists,includingLeonardodaVinci,refusedtousethecameraobscurabecauseitwastoodifficulttooperate.

F.Theprojectedimagefromacameraobscuraisalwaysuprightandnon-reversed.

Passage3

TheEconomicSpecializationoftheAncientMayaCivilization

TheancientMayacivilization,whichflourishedinMesoamericafromapproximately2000BCEto900CE,isrenownedforitsmonumentalarchitecture,intricatecalendricalsystems,andsophisticatedwriting.However,recentarchaeologicalresearchhasshedlightonanothercrucialaspectofMayasociety:itscomplexeconomy.Farfrombeingacollectionofisolated,self-sufficientagriculturalvillages,theMayalowlandssupportedahighlyinterconnectednetworkoftradeandeconomicspecialization.Thisnetworkfacilitatedtheexchangeofgoods,ideas,andcultureacrossvastdistances,contributingtothepoliticalintegrationanddominanceofeliteMayacity-states.

TheMayaeconomywasfundamentallyagrarian,withmaizeservingasthestaplecrop.However,theenvironmentoftheMayalowlandspresentedchallenges.Theregionischaracterizedbyatropicalclimatewithadistinctwetanddryseason,andsoilsareoftenthinandnutrient-poor.Tosustainlargepopulations,theMayadevelopedintensiveagriculturaltechniquessuchasterracing,raisedfields,andirrigationsystems.Theseinnovationsallowedforsurplusproduction,whichwasessentialtosupportnon-farmingspecialists.Thecontrolofagriculturalsurplusesandthemeansofproductionbecameaprimarysourceofpowerfortherulingelite.

Asurbancentersgrew,sodidthedemandforspecializedcraftgoods.Artisansproduceditemssuchasobsidiantools,jadeornaments,finelypaintedceramics,andwoventextiles.Obsidian,avolcanicglass,wasparticularlyvaluedforitsrazor-sharpedges,usedinweaponsandritualbloodletting.SincetheMayalowlandslackvolcanicsources,obsidianhadtobeimportedfromhighlandGuatemalaandcentralMexico.Thistraderequiredlong-distanceexchangenetworksandtheorganizationofcaravans.Theflowofobsidianandotherprestigegoodswaslargelycontrolledbytheelite,whousedtheseitemstoreinforcetheirstatusandpoliticalalliancesthroughredistributionandgifting.

Economicspecializationwasnotlimitedtocraftproduction.TheMayaalsoengagedinresourceextractionandprocessing.Salt,acriticalnecessityfordietpreservation,wasproducedalongthecoastsoftheYucatanPeninsula.Archaeologicalevidencesuggeststhatsaltproductionwasaspecializedactivity,withspecificworkshopsdedicatedtoboilingbrinetoproducesaltcakes.Thesesaltcakeswerethentradedinlandtotheforestcommunities.Similarly,theproductionoflime,usedforplasteringpyramidsandresidentialfloors,requiredspecializedknowledgeofburninglimestone.Thisindicatesadivisionoflaborwherecertaingroupsorcommunitiesfocusedonspecificindustriestoservethebroaderregionaleconomy.

ThemarketplacewasanothervitalcomponentoftheMayaeconomicsystem.Earlyethnohistoricaccounts,suchasthosebyBishopDiegodeLanda,describedbustlingmarketsinMayacitieswhereawidevarietyofgoodswereexchangedusingcacaobeansascurrency.Forcenturies,archaeologistsdebatedtheexistenceofformalmarketplacesintheClassicperiod,astheyaredifficulttoidentifyarchaeologically.However,recentdiscoveriesofplazaswithspecializedlayoutdesignsandthedistributionofgoodsconsistentwithmarketexchangehaveconfirmedtheirpresence.Thesemarketsallowedforthecirculationofeverydaygoods,suchasfoodstuffsandpottery,freeingtheelitefromhavingtomicromanagethedistributionofallresources.

Theintegrationofthiseconomyreliedheavilyonthepoliticalauthorityofthekingsandthedivineright.TheMayarulersclaimedcosmicauthority,associatingthemselveswithgodsandthecyclesoftime.Thisreligiouslegitimacyjustifiedtheircontrolovertraderoutesandthemobilizationoflaborformonumentalconstructionprojects.ThecollapseoftheClassicMayapoliticalstructuresinthe9thcenturyCEledtothefragmentationofthiseconomicnetwork.Thedeclineoflong-distancetradeandtheabandonmentofurbancenterssuggestthatthespecializedeconomywasintrinsicallylinkedtothestabilityandcentralizationofpoliticalpower.

21.Theword"agrarian"inparagraph2isclosestinmeaningto

A.industrial

B.relatedtofarming

C.military

D.urban

22.Accordingtoparagraph2,whatwasoneresultoftheagriculturalinnovationsdevelopedbytheMaya?

A.TheyallowedtheMayatoexportmaizetoEurope.

B.Theyenabledthesupportofnon-farmingspecialists.

C.Theycausedthesoiltobecomenutrient-rich.

D.Theyeliminatedtheneedforadistinctwetanddryseason.

23.Whydoestheauthormentionobsidianinparagraph3?

A.Toillustratetheimportanceoflong-distancetradeandelitecontroloverluxurygoods.

B.ToprovethattheMayalowlandshadabundantvolcanicresources.

C.ToexplainwhytheMayamilitarywassuperiortoitsneighbors.

D.ToshowthattheMayaonlyusedtoolsmadeofstoneandmetal.

24.Theword"prestige"inparagraph3isclosestinmeaningto

A.status

B.heavy

C.common

D.useless

25.Accordingtoparagraph4,whichofthefollowingwasaspecializedindustryinancientMayasociety?

A.Thecultivationofmaize.

B.Theproductionofsalt.

C.Theconstructionofroads.

D.Thewritingofhistorybooks.

26.Whatcanbeinferredfromparagraph5abouttheroleofmarketplacesinMayasociety?

A.Theywereonlyusedfortradingluxuryitemslikejadeandgold.

B.Theyoperatedwithoutastandardizedcurrency.

C.Theyfacilitatedtheexchangeofdailynecessitiesandreducedtheelite'sburdenofresourcedistribution.

D.Theywerelocatedonlyinthehighlandregions.

27.Theword"intrinsically"inthefinalparagraphisclosestinmeaningto

A.barely

B.essentially

C.optionally

D.superficially

28.Accordingtothepassage,whatfactorcontributedtothecollapseoftheMayaeconomicnetwork?

A.Thedepletionofthecacaobeansupply.

B.TheinvasionofforeignarmiesfromEurope.

C.Thebreakdownofcentralizedpoliticalauthority.

D.Thetransitionfromanagrariantoanindustrialeconomy.

29.Lookatthefourletters[A,B,C,D]thatindicatewherethefollowingsentencecouldbeaddedtothepassage.

"Thesemarketsallowedforthecirculationofeverydaygoods,suchasfoodstuffsandpottery,freeingtheelitefromhavingtomicromanagethedistributionofallresources."

Wherewouldthesentencebestfit?

A.Earlyethnohistoricaccounts,suchasthosebyBishopDiegodeLanda,describedbustlingmarketsinMayacitieswhereawidevarietyofgoodswereexchangedusingcacaobeansascurrency.[A]

B.Forcenturies,archaeologistsdebatedtheexistenceofformalmarketplacesintheClassicperiod,astheyaredifficulttoidentifyarchaeologically.[B]

C.However,recentdiscoveriesofplazaswithspecializedlayoutdesignsandthedistributionofgoodsconsistentwithmarketexchangehaveconfirmedtheirpresence.[C]

D.Theintegrationofthiseconomyreliedheavilyonthepoliticalauthorityofthekingsandthedivineright.[D]

30.Directions:CompletethetablebelowbymatchingFOURofthefiveanswerchoiceswiththeeconomicactivityorfeaturethatitcharacterizes.Thisquestionisworth3points.

EconomicActivities/Features

Descriptions

Controlledlargelybytheelite

A.Involvedadivisionoflaborandworkshops

Long-distancetrade

B.Enabledthesupportofartisansandrulers

Marketplaceexchange

C.Reliedoncacaobeansascurrency

Agriculturalproduction

D.Facilitatedtheexchangeofobsidianandjade

E.Wassolelymanagedbylocalfarmerswithoutcentraloversight

AnswersandExplanations

Passage1:TheRoleofPermafrostinGlobalCarbonCycling

1.B."anthropogenic"referstosomethingthatiscausedbyhumans,particularlyinthecontextofpollutionorclimatechange.

2.B.Thepassagestatesthatbecausethegroundremainedfrozen,microbialactivitywashalted,whichpreventeddecompositionandallowedcarbontoaccumulate.

3.B.ThehighlightedsentenceexplainsthatmethaneisproducedinanaerobicconditionsandismuchmorepotentthanCO2.OptionBcapturesthiscomparisonandthecausallink.

4.B."Magnitude"inthiscontextreferstothesize,scale,orextentofthecarbonrelease.

5.C.Paragraph3explainsthatmethaneisproducedinanaerobic(water-saturated)environments,whilecarbondioxideisproducedinaerobic(oxygen-rich)environments.

6.A."Arcticgreening"ismentionedasafactorthatlowersalbedo(reflectivity),causingthegroundtoabsorbmoreheat,whichleadstofurtherwarmingandpermafrostdegradation.Thisisapositivefeedbackloop.

7.C.Thepassagementionsdamagetoinfrastructure(roads,pipelines),changesinvegetation(shrubs),andgreenhousegasrelease.Itdoesnotmentionvolcanicactivity.

8.C.Thesentence"Consequently,thiscarbonremainedsequestered"logicallyfollowstheexplanationthatmicrobialactivitywashaltedduetothefrozenground.Itexplainstheresultofthehaltedactivity.

9.C."Sequestered"meansisolatedandstoredaway.Inthecontextofcarbon,itmeanstrappedintheground.

10.Summary:A,B,D

Aiscorrect:Thepassageemphasizesthevastamountofcarbonstoredinpermafrost.

Biscorrect:ThereleaseofmethaneandCO2isthecentralmechanismofthefeedbackloop.

Discorrect:Physicalchangeslikegroundinstabilityandvegetationchangesarediscussedasconsequencesthatfurtherexacerbatewarming.

Cisincorrect:Thermokarstlakesarecausedbythawingice,notanimalmigration.

Eisincorrect:Thepassagestatesthereareuncertainties,andsomemodelssuggestabruptthawing,notjustgradual.

Fisincorrect:Bothmethaneandcarbondioxidearereleased.

Passage2:TheDevelopmentoftheCameraObscurainRenaissanceArt

11.A."Phenomenon"referstoanaturaloccurrenceorfactthatisobservable.

12.C.Paragraph2statesthatlensessharpenedtheprojectedimageandallowedformoreprecisetracing.

13.B.The"Hockney-Falcothesis"isdescribedastheargumentthattheriseofopticalrealismwaslargelyduetotheuseofopticalprojectionslikethecameraobscura.

14.C."Anomalies"referstothingsthataredeviatingfromthegeneralruleorstandard.Inthiscontext,itreferstospecificvisualfeaturesinpaintingsthatdifferfromwhatoneexpectsfrommanualdrawing.

15.B.Thepaintingisusedasevidencetosupportthetheorythatopticaldeviceswereusedbecauseitshows"depthoffield"(blurredforeground,sharpmiddledistance),acharacteristicoflenses,nothumanvision.

16.C.Criticsarguethattherealismwasachievedthroughrigorousstudyofanatomy,geometry,andperspectivesystems,ratherthanrelyingsolelyonopticaltools.

17.C.Thepassageasawholedescribeshowascientificdevice(cameraobscura)influencedart(realism,perspective),suggestinganintersectionofthetwofields.

18.C.Thesentencedescribestheresultofaddinglenses.Itfitsbestafterthesentencementioninglenseswereaddedandbeforethesentencedescribingthedevicetypes.

19.A."Pleinair"isaFrenchtermm