Which Man clsss properly represents the relationship "Man has a best friend who is a Dog"？（）

A、AclassManextendsDog{}
B、BclassManimplementsDog{}
C、CclassMan{privateBestFrienddog；}
D、DclassMan{privateDogbestFriend；}
E、EclassMan{privateDog；}
F、FclassMan{privateBestFriend；}