[单选题]II.Reading.(2x4=8)TheUnitedStatesandCanadahaveagreedtokeeptheirsharedborderclosedfornonessentialtravelforanother30daystopreventthespreadofthecoronavirus.CanadianPrimeMinisterJustinTrudeauannouncedtheextensionduringabriefingSaturdayinOttawa.Therestrictionsontheworld’slongestfrontiertookeffectonMarch21,whileallowingtradeandothertraveldeemedessentialtocontinue.Thepartialbanwastoexpiresoon,buttheneighboringcountrieshavedecideditisnotsafetoallowtraffictofullyresume.“Thisisanimportantdecisionandonethatwillkeeppeopleonbothsidesofthebordersafe,”Trudeautoldanewsconferenceoutsidetheresidencewherehehasbeenlivingandworkinginrecentweeks.Canada,withapopulationofunder38million,hashadmorethan32,000casesofinfectionand1,340deathsfromCOVID-19,asofSaturday.TheU.S.hasidentifiedalmost720,000casesandover37,000deaths,asoflateSaturdayafternoon.SeveralofAmerica’shardest-hitareasincludingNewYorkstateshareaborderwithCanadianprovinces.Bothcountrieshavetestingshortages.Bordercrossingshavefallendramatically,evendespitetheessentialtravelexemptions.AtthePeaceBridgebetweenBuffalo,N.Y.,andFortErie,Ontario,“passengertraffic[is]down95%,bustrafficdown...99.6%,soessentially,it’sshutdown,”KathrynFriedman,aglobalfellowattheWilsonCenter’sCanadaInstitute,saidinaconferenceTuesday.“Commercialtrafficisdownalittleover28%.”“Itissurrealtoseesuchlittletraffic,”RonRienas,whorunstheauthoritythatmanagesthePeaceBridge,toldTheBuffaloNews.SinceApril1,tunneltrafficbetweentheheavilyintegratedDetroitandWindsor,Ontarioregionsisdown88%overthesameperiodlastyear,accordingtoFriedman.ConcernshaveriseninCanadaaboutdailytripsbyaround1,600healthcareworkersfromOntariotohard-hitDetroit.SomenurseswhoworkinfacilitiesinboththeU.S.andCanadahavehadtochooseone.Theextensionoftheborderrestrictionscameafteraweekinwhichthegovernmentsgavemixedsignalsaboutthenextstep.PresidentTrumpsaidonWednesdaythattheCanadianborder“willbeoneoftheearlyborderstobereleased.Canadaisdoingwell.We’redoingwell.”Butthenextday,PrimeMinisterTrudeautoldreporters,“Thereisasignificantamountoftime,still,beforewecantalkaboutlooseningsuchrestrictions.”6.WhendidTrudeauannouncetheextension?
