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