请阅读Passagel，完成第下列问小题。
Passage1
Trafficlightsarecrucialtoolsforregulatingtrafficflow.Theyarenot,however,perfect.
Driversexchangethegridlockthatwouldhappenatunmanagedjunctionsforapatternofstop-gomovementthatcanstillbefrustrating,andwhichburnsmorefuelthanasmoothpassagewould.
Creatingsuchasmoothpassagemeansadjustingavehicle′sspeedsothatitalwaysarrivesatthelightswhentheyaregreen.Thatistheoreticallypossible,butpracticallyhard.Roadsidesignswiredtotrafficlightsmayhelp,buttheyhavenotbeenwidelydeployed.Nowscientistshaveanideathatcouldmaketheprocesscheaperandmoreeffective.Insteadofahardwirednetworkofsigns,theyproposetousemobile-phoneapps.
Foradrivertobenefit,hemustloadaspecialsoftware,dubbedSignalGuru,intohisphoneandthenmountitonaspecialbracketattachedtotheinsideofhiscar′swindscreen,withthecameralenspointingforwards.SignalGuruisdesignedtodetecttrafficlightsandtracktheirstatusasred,amberorgreen.Itbroadcaststhisinformationtootherphonesintheareathatarefittedwiththesamesoftware,and--ifthereareenoughofthem--thephonesthuseachknowthestatusofmostofthelightsaroundtown.Usingthisinformation,SignalGuruisabletocalculatethetraffic-lightschedulefortheregionandsuggestthespeedatwhichadrivershouldtravelinordertoavoidrunningintoredlights.
TestsinCambridge,Massachusetts,wherefivedriverswereaskedtofollowthesamerouteforthreehours,andinSingapore,whereeightdriverswereaskedtofollowoneoftworoutesfor30minutes,revealedthatSignalGuruwascapableofpredictingtraffic-lightactivitywithanaccuracyof98.2%and96.3%respectively,inthetwocities.ThiswasparticularlyimpressivebecauseinCambridgethelightsshifted,roughlyhalf-waythroughthetest,fromtheiroff-peakscheduletotheirafternoon-trafficschedule,whileinSingaporelightsareadaptive,usingdetectorsembeddedundertheroadtodeterminehowmuchtrafficisaroundandthuswhenasignalshouldchange.Fuelconsumptionfell,too--byabout20%.SignalGuruthusreducesbothfrustrationandfueluse,andmakescommutingaslightlylesshorribleexperience.
{TS}Whatdodriversdoiftheywanttopassunmanagedjunctionssmoothly?

A.Theymustwaitpatientlyuntiltrafficlightsturngreen.

B.Theyneedtohelptrafficpolicetoregulatetrafficflows.

C.Theycandrivethroughtheredlightsifnobodyisaround.

D.Theyhavetoadjustthespeedintimeforthegreenlights.