What should you do if you receive an email telling you that you have won a competition you did not enter?

A、Openthemessageandclaimtheprize.;
B、Openthemessagetoseeiftheprizeisworthclaiming.;
C、Contactthesenderoftheemailandtellhimhehasmadeamistake.;
D、Deletethemailimmediately.