Whichtwostatementscorrectlydescribetherelationbetweenadatafileandthelogicaldatabasestructures()

A.Anextentcannotspreadacrossdatafiles.

B.Asegmentcannotspreadacrossdatafiles.

C.Adatafilecanbelongtoonlyonetablespace.

D.Adatafilecanhaveonlyonesegmentcreatedinit.

E.Adatablockcanspreadacrossmultipledatafilesasitcanconsistofmultipleoperatingsystem（OS）blocks