Creating References Using Inheritance Hierarchies

public class Animal { public String s() { return "?"; } }
public class Dog extends Animal { public String s() { return "Woof"; } }
public class Cat extends Animal { public String s() { return "Meow"; } }
Animal[] arr = { new Dog(), new Cat(), new Animal() };
for (Animal a : arr) System.out.print(a.s() + " ");

• A

  Woof Meow ?

  check_circle
• B

  Woof Woof Woof

• C

  ? ? ?

• D

  Compile-time error