【单选题】Mostforestfiresarecausedbyhumancarelessness,negligence,orignorance.Forestfireprevention,therefore,ismainlyaproblemofcreatingabetterunderstandingoftheimportanceofforests,anawarenessofthedangeroffireinthewoods,andasenseofpersonalresponsibilitytosafeguardtheforestsfromdanger.ThisisnotaneasyjoB、A、citydweller,usedtopavedstr eets,doesnoteasilychangehissmokinghabitswhenhegoesintothewoods.Carelesssmokersareresponsibleforthousandsofforestfireseachyear.Manyofthesearestartedwhencigarettebuttsandmatchesarethrownfromautomobiles.Othersarecausedbyhunters,hikers,fishermen,orwoodsworkerswhoarecarelessindisposingoftheirsmokingmaterials.TheForestServicehaspostedrulesinmanyoftheNationalForeststhatprohibitsmokingexceptincertaindesignatedareas.Manyofthestateshavelawsagainstthrowinglightedmaterialsfromautomobiles.Thepreventionofsmoker-causedfires,however,dependsuponchangingtheattitudesandbehaviorofmillionsofpeoplewhosmokeinhazardousareas.Themostimportantnaturalcauseoffireislightning.Thisaccountsfor11percentofforestfiresonprotectedlandfortheentirenation;inthewesternStates,lightningcausesamuchhigherpercentageoffiresthanitd oesintheEast.Advancesinknowledgeoffireweatherarehelpingforestprotectionforcestoknowwhentobealertforlightning-causedfires.Adequateandwell-equippedforcescancontr olthemquicklyandholdthedamagetoaminimum.Experimentsin"seeding"thundercloudstopreventorcontr olthelightningitselfhavebeeninprocessformanyyears,butnewbreakthroughsareneededforanysignificantr eductioninthelightning-causedfires.Whichofthefollowingstatementsistr ueA、Theconservationofforestsisn’taneasytask.B、Inforestssmokingisprohibitedinafewsafeareas.C、Lightning,theonlynaturalcause,accountsfor11%oftheforestfiresintheWesternStates.D、Newbreakthroughscan’tbeexpectedfromexperimentsin"seeding"thunderclouds.
【单选题】Mostforestfiresarecausedbyhumancarelessness,negligence,orignorance.Forestfireprevention,therefore,ismainlyaproblemofcreatingabetterunderstandingoftheimportanceofforests,anawarenessofthedangeroffireinthewoods,andasenseofpersonalresponsibilitytosafeguardtheforestsfromdanger.ThisisnotaneasyjoB、A、citydweller,usedtopavedstr eets,doesnoteasilychangehissmokinghabitswhenhegoesintothewoods.Carelesssmokersareresponsibleforthousandsofforestfireseachyear.Manyofthesearestartedwhencigarettebuttsandmatchesarethrownfromautomobiles.Othersarecausedbyhunters,hikers,fishermen,orwoodsworkerswhoarecarelessindisposingoftheirsmokingmaterials.TheForestServicehaspostedrulesinmanyoftheNationalForeststhatprohibitsmokingexceptincertaindesignatedareas.Manyofthestateshavelawsagainstthrowinglightedmaterialsfromautomobiles.Thepreventionofsmoker-causedfires,however,dependsuponchangingtheattitudesandbehaviorofmillionsofpeoplewhosmokeinhazardousareas.Themostimportantnaturalcauseoffireislightning.Thisaccountsfor11percentofforestfiresonprotectedlandfortheentirenation;inthewesternStates,lightningcausesamuchhigherpercentageoffiresthanitd oesintheEast.Advancesinknowledgeoffireweatherarehelpingforestprotectionforcestoknowwhentobealertforlightning-causedfires.Adequateandwell-equippedforcescancontr olthemquicklyandholdthedamagetoaminimum.Experimentsin"seeding"thundercloudstopreventorcontr olthelightningitselfhavebeeninprocessformanyyears,butnewbreakthroughsareneededforanysignificantr eductioninthelightning-causedfires.Whichofthefollowingstatementsistr ueA、Theconservationofforestsisn’taneasytask.B、Inforestssmokingisprohibitedinafewsafeareas.C、Lightning,theonlynaturalcause,accountsfor11%oftheforestfiresintheWesternStates.D、Newbreakthroughscan’tbeexpectedfromexperimentsin"seeding"thunderclouds.



