题目内容：
Questionsarebasedonthefollowingpassage. Scratchythroats,stuffynosesandbodyachesallspellmisery,butbeingabletotellifthecauseisacoldorflu（流感）maymakeadifferenceinhowlongthemiserylasts.
TheAmericanLungAssociation（ALA）hasissuednewguidelinesoncombatingcoldsandtheflu,andoneofthekeysisbeingabletoquicklytellthetwoapart.That’sbecausetheprescriptiondrugsavailableforthefluneedtobetakensoonaftertheillnesssetsin.Asforcolds,thesoonerapersonstartstakingover-the-counterremedy,thesoonerreliefwillcome.
Thecommoncoldandthefluarebothcausedbyviruses.Morethan200virusescancausecoldsymptoms,whilethefluiscausedbythreeviruses—fluA,BandC.Thereisnocureforeitherillness,buttheflucanbepreventedbythefluvaccine（疫苗）,whichis,formostpeople,thebestwaytofighttheflu,accordingtotheALA.
Butifthefludoesstrike,quickactioncanhelp.Althoughthefluandcommoncoldhavemanysimilarities,therearesomeobvioussignstolookfor.
Coldsymptomssuchasstuffynose,runnynoseandscratchythroattypicallydevelopgradually,andadultsandteensoftendonotgetafever.Ontheotherhand,feverisoneofthecharacteristicfeaturesofthefluforallages.Andingeneral,flusymptomsincludingfeverandchills,sorethroatandbodyachescomeonsuddenlyandaremoreseverethancoldsymptoms.
TheALAnotesthatitmaybeparticularlydifficulttotellwheninfantsandpreschoolagechildrenhavetheflu.Itadvisesparentsto
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