quEstions 16 to 20 ArE BAsED on thE Following tAlk.

A、thE moDErn ElECtroniC Anti-noisE DEviCEs ArE An upDAtE vErsion oF thE trADitionAl mEthoDs.
B、thE moDErn ElECtroniC Anti-noisE DEviCEs shArE similAritiEs with thE trADitionAl mEthoDs.
C、thE moDErn ElECtroniC Anti-noisE DEviCEs ArE As inEFFiCiEnt As thE trADitionAl mEthoDs.
D、thE moDErn ElECtroniC Anti-noisE DEviCEs ArE BAsED on An EntirEly nEw working prinCiplE.