The author states that the research described
问题详情
The author states that the research described in the first paragraph was undertaken in order to______
A．determine the age of an actual meteor stream
B．Identify the various structural features of meteor streams
C．explore the nature of a particularly interesting meteor stream
D．test the hypothesis that meteor streams become broader as they age
E．show that a computer model could help in explaining actual astronomical data请帮忙给出正确答案和分析，谢谢！
参考答案
正确答案：D
解析：Thisquestionaskswhattheauthorsaysaboutthepurposeoftheresearchdescribedinthefirstparagraph.ThebestanswerisD.Accordingtotheauthor,thepurposeofthecomputer-modelingexperimentwastotestthehypothesisthatmeteorstreamsbroadenwithtime.ChoiceAisnotcorrect;althoughtheobservationaldatadescribedinthelastparagraphallowedscientiststoestimatetheageoftheGeminidstream,thisdatawasanalyzedtoconfirmasurprisingpredictionmadebythecomputermodel.Thisanalysiswasnotpartoftheoriginalexperiment.ChoiceBisalsoincorrect.Althoughtheexperimentyieldedasurprisingpredictionaboutaparticularfeatureofmeteorstreams,thepurposeoftheexperimentwastodeterminewhethermeteorstreamsbroadenwithtime,nottoidentifythevariousstructuralfeaturesofmeteorstreams.ChoiceCisnotcorrectbecausetheexperimentwasundertakentotestageneralhypothesisaboutmeteorstreams.Itwasnotundertakentoexplorethenatureofanyparticularmeteorstream,andthepassageneversuggeststhattheactualmeteorstreamsusedinthecomputermodelwas“particularlyinteresting.”ChoiceEisnotcorrect.Althoughthecomputermodeldidconfirmtheastronomers’hypothesis,thepurposeoftheexperimentwasnottoshowthatsuchmodelsareuseful.
