下面哪个类实现了接口Usable? interface Usable { int eat(int data); }
A.
class Human implements Usable{ int use(int a) { return 1; } }
B.
class Human extends Usable { public int use(int a) { return 1;} }
C.
class Human implements Usable{ public int use(int a) { return 1;} }
D.
class Human implements Usable{ public int use() { return 1;} }