Certificatesare(请作答此空)documentsattestingtothe()ofapublickeytoanindividualorotherentity.Theyallowverificationoftheclaimthatagivenpublickeydoesinfactbelongtoagivenindividual.Certificateshelppreventsomeonefromusingaphonykeyto()someoneelse.Intheirsimplestform,Certificatescontainapublickeyandaname.Ascommonlyused,aCertificatealsocontainsan()date,thenameoftheCAthatissuedtheCertificate,aserialnumber,andperhapsotherinformation.Mostimportantly,itcontainsthedigital()ofthecertificateissuer.ThemostwidelyacceptedformatforcertificatesisX.509,thus,CertificatescanbereadorwrittenbyanyapplicationcomplyingwithX.509.
A.text B.data] C.digital D.structured]正确答案C
