【单选题】Which Man class properly represents the relationship "Man has a best friend who is a Dog"?()
A.
class Man extends Dog { }
B.
class Man implements Dog { }
C.
class Man { private BestFriend dog; }
D.
class Man { private Dog bestFriend; }
E.
class Man { private Dog ; }
F.
class Man { private BestFriend ; }