10.interfaceFoo{}11.classAlphaimplementsFoo{}12.classBetaextendsAlpha{}13.classDeltaextendsBeta{14.publicstaticvoidmain（String[]args）{15.Betax=newBeta（）；16.//insertcodehere17.}18.}Whichcode，insertedatline16，willcauseajava.lang.ClassCastException？（）
A.Alphaa=x；
B.Foof=（Delta）x；
C.Foof=（Alpha）x；
D.Betab=（Beta）（Alpha）x；

单项选择题YouworkinacompanywhichusesSQLServer2008.Youaretheadministratorofthecompanydatabase.NowyouareinchargeofaSQLServer2008instance.ThereisadatabasenamedDB1intheinstance.TheDB1databaseincludesspatialdatatypes.OnDB1databse,youhavetoperformadatabaseconsistencychecktoincludethespatialindexes.Besidesthis,youmustmakesurethatyoucanreducetheeffectonthedatabaseconcurrencytotheleast.SowhichTransact-SQLstatementshouldyourun?（）A.DBCCCHECKCATALOG(DB1);B.DBCCCHECKALLOC(DB1)WITHTABLOCK;C.DBCCCHECKDB(DB1)WITHTABLOCK,PHYSICAL_ONLY;D.DBCCCHECKDB(DB1)WITHEXTENDED_LOGICAL_CHECKS;

单项选择题Yourcompanyhasamainofficeandthreebranchoffices.ThecompanyhasanActiveDirectoryforestthathasasingledomain.Eachofficehasonedomaincontroller.EachofficeisconfiguredasanActiveDirectorysite.AllsitesareconnectedwiththeDEFAULTIPSITELINKobject.Youneedtodecreasethereplicationlatencybetweenthedomaincontrollers.Whatshouldyoudo（）A.Decreasethecostbetweentheconnectionobjects.B.Decreasethereplicationintervalforallconnectionobjects.C.DecreasethereplicationintervalfortheDEFAULTIPSITELINKobject.D.DecreasethereplicationschedulefortheDEFAULTIPSITELINKobject.

单项选择题YouareimplementinganASP.NETpage.ThepageincludesamethodnamedGetCustomerOrderDataSetthatreturnsaDataSet.TheDataSetincludesaDataTablenamedCustomerDetailsTableandaDataTablenamedOrderDetailsTable.YouneedtodisplaythedatainOrderDetailsTableinaDetailsViewcontrolnameddtlView.Whichcodesegmentshouldyouuse？（）A.dtlView.DataSource=GetCustomerOrderDataSet（）；dtlView.DataMember= OrderDetailsTable ；dtlView.DataBind（）；B.dtlView.DataSource=GetCustomerOrderDataSet（）；dtlView.DataSourceID= OrderDetailsTable ；dtlView.DataBind（）；C.dtlView.DataSource=GetCustomerOrderDataSet（）；dtlView.DataKeyNames=newstring[]{ OrderDetailsTable }；dtlView.DataBind（）；D.DataSetdataSet=GetCustomerOrderDataSet（）；dtlView.DataSource=newDataTable（ dataSet ， OrderDetailsTable ）；dtlView.DataBind（）；

单项选择题YourcompanyhasanActiveDirectorydomain.AllserversrunWindowsServer2008.YourcompanyusesanENterpriseRootcertificationauthority（CA）andanEnterpriseIntermediateCA.TheEnterpriseintermediateCAcertificateexpires.YouneedtodeployanewEnterpriseIntermediateCAcertificatetoallcomputersinthedomain.Whatshouldyoudo（）A.ImportthenewcertificateintotheIntermediateCertificationStoreontheEnterpriseRootCAserver.B.ImportthenewcertificateintotheIntermediateCertificationStoreontheEnterpriseIntermediateCAserver.C.ImportthenewcertificateintotheIntermediateCertificationStoreintheDefaultDomainControllersgroupobject.D.ImportthenewcertificateintotheIntermediateCertificationStoreintheDefaultDomaingrouppolicyobject.

单项选择题Youneedtodeployaread－onlydomaincontroller（RODC）thatrunsWindowsServer2008.Whatistheminimalforestfunctionallevelthatyoushoulduse（）