题目内容：
BWhenmybrotherandIwereyoung,mymomwouldtakeusonTransportationDays.
Itgoeslikethis:Youcan'ttakeanymeansoftransportationmorethanonce.Wewouldstartfromhome,walkingtwoblockstotherailstation.We'dtakethetraininto
thecitycenter,thenabus,switchingtothetram,thenmaybeataxi.Wealways
consideredtakingahorsecarriageinthehistoricdistrict,butwedidn'tliketheway
thehorsesweretreated,soweneverdid.Attheendoftheday,wetookthesubwayto
ourcloseststation,whereMom'sfriendwaswaitingtogiveusaridehome-ourfirst
carrideoftheday.
ThegoodthingaboutTransportationDaysisnotonlythatMomtaughtushowtogetaround.Shewasborntobemultimodal(多方式的).Sheunderstoodthat
dependingoncarsonlywasafailureofimaginationand,aboveall,afailureof
confidence-theproductofachildhoodnotspentexploringsubwaytunnels.
OnceyouIeamtheroutemapandstepwithcertaintyoverthegapbetweenthetrainandtheplatform,nothingisfrighteninganymore.Newcitiesarejustlight-raillinestobeexplored.Andyourpersonalcar,ifyouhaveone,becomesjustonemoretoolinthetoolbox-andoftenaninadequateone.limitingbothyournobilityandyourwallet.
OnTransportationDays,wemightstopforlunchonChc.rnwSurdorbuyanewbookortoy.butthetransportationwasthepoint.First,itwasexcitingenoughtowatchtheworldspeedbyfromthetrainwindow.AsIgotolder,mymomhelpedmeunlockthemysteriesthatwouldotherwisehaveparalyzedmyfirstattemptstodoitmyself.HowdoIknowwheretogetoff?HowdoIknowbowmuchitcosts?HowdoIknowwhenIneedtickets,andwheretogetthem?Whattrack.whatline.Whichdirection,where'sthestop,andwillIgetwetwhenwegoundertheriver?
I'mwritingthisrightnowonanairplane.amean,wedidn'ttryonourTransportationDaysand.wenowknow,thedirtiestandmostpollutingofthemall.MyflighttoutedmethroughPhiladelphia.Mymultimoda1mommetmefordinnerinTheairport.Shetookatrainmmeetme.WhichwasforbiddenbyMmonTransportationDays? A．Havingacarrid
B．Takingthetraintwic
C．Buyingmoredmateto
D．Touringthehistoricdistric
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