It can be inferred from the last paragraph of
问题详情
It can be inferred from the last paragraph of the passage that which of the following must be true of the Earth as it orbits the Sun？
A．Most meteor streams it encounters are more than 2,000 years old.
B．When passing through a meteor stream, it usually passes near to the stream’s center.
C．It crosses the Geminid meteor stream once every year.
D．It usually takes over a day to cross the actual Geminid meteor stream.
E．It accounts of msot of the gravitaitonal perturbation affecting the Geminid meteor stream.请帮忙给出正确答案和分析，谢谢！
参考答案
正确答案：C
解析：Thisquestionasksyoutodrawaninferencefrominformationinthelastparagraphofthepassage.ThebestanswerisC.Accordingtothepassage,theGeminidmeteorshoweroccursyearly;becausemeteorshowersoccurwhenevertheEarthpassesthroughameteorstream,onecaninferthattheEarthcrossestheGeminidstreamonceeveryyear.ChoiceAisincorrectbecausethepassageprovidesnoinformationfromwhichtogeneralizeabouttheageofmeteorstreams.ChoiceB,whichisdirectlycontradictedbylines31-32,isalsoincorrect.ChoiceDisincorrect.Inlines25-28,thepassagesaysthattheEarthwouldtakejustoveradaytocrossthestreamifthestreamwere5,000yearsold.However,inlines38-42thepassagestatesthatinfactanaverageofonly19houseselapsedbetweenthetimethattheEarthenteredthestreamuntilthetimethatitexited,leadingresearcherstoconcludethatthestreamisonlyabout3,000yearsold.ChoiceEisincorrectbecausethepassagesaysonlythatplanetarygravitationalfieldsperturbtheorbitsofdustparticlesinameteorstream;itdoesnotsaythattheeffectoftheEarth’sgravitationisgreaterthanthatofotherplanets.
