向被攻击对象网络服务器或工作站发送3vN-无用的且要求回复的信息，以消耗其网络带宽或系统资源，从而使被攻击对象的网络或系统无法负荷以致瘫痪的攻击方式叫做（）
Inwhatseemsliketheprehistorictimesofcomputerhistory;theearth’spostwarera,therewasquiteawidespreadrumorthatcomputerswouldtakeovertheworldfrommanoneday.Alreadytoday,lessthanfiftyyearslater,ascomputersarerelievingusofmoreandmoreoftheroutinetasksinbusinessandinourpersonallives,wearefacedwithalessdramaticbutnotlessforeseenproblem.Peopletendtobeover-trustingofcomputersandarereluctanttochallengetheirauthority.Indeed,theybehaveasiftheywerehardlyawarethatwrongbuttonsmaybepushed,orthatacomputermaysimplymalfunction.Obviously,therewouldbenopointininvestinginacomputerifyouhadtocheckallitsanswers,butpeopleshouldalsorelyontheirowninternalcomputersandcheckthemachinewhentheyhavethefeelingthatsomethinghasgonewrong.Questioningandroutinedouble-checksmustcontinuetobeasmuchapartofgoodbusinessastheywereinpre-computerdays.Maybeeachcomputershouldcomewiththewarning:forallthehelpthiscomputermayprovide,itshouldnotbeseenasasubstituteforfundamentalthinkingandreasoningskills.
37.Accordingtothepassage,theauthorwouldprobablydisapproveof__________.
A.investmentincomputers
B.completedependenceoncomputers
C.double-checkoncomputers
D.theuseofcomputer
38.Intheauthor’sopinion,peopleshould__________.
A.bereasonablydoubtfulaboutcomputers
B.usecomputersforbusinesspurposesonly
C.substitutecomputersforbasicthinking
D.checkalltheiranswerswhenusingcomputers
39.Whatissuggestedinthispassage?
A.Computerwon’tchangeourpersonallives.
B.Computercancreateunforeseenproblems.
C.Computerhastakencontroloftheworld.
D.Computercannotaffectourbusinesses.
40.Whatisthemainpurposeofthispassage?
A.Tolookbacktotheearlydaysofcomputers.
B.Toexplainwhattechnicalproblemsmayoccurwithcomputers.
C.Todiscourageinvestmentincomputers.
D.Towarnagainstamentallylazyattitudetowardscomputers.