多项选择题

A. Cat is-a JumperB. Cat is-a AnimalC. Dog is-a JumperD……

Given：
10. interface Jumper { public void jump（）； } ...
20. class Animal {} ...
30. class Dog extends Animal {
31. Tail tail；
32. }
...
40. class Beagle extends Dog implements Jumper{
41. public void jump（） {}
42. }
...
50. class Cat implements Jumper{
51. public void jump（） {}
52. }.
Which three are true？（）

A. Cat is-a Jumper
B. Cat is-a Animal
C. Dog is-a Jumper
D. Dog is-a Animal
E. Beagle has-a Jumper
F. Cat has-a Animal
G. Beagle has-a Tail

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