Creating References Using Inheritance Hierarchies

AP Computer Science A· difficulty 3/5

public class Animal {}
public class Dog extends Animal {
    public void bark() { System.out.print("Woof"); }
}
Animal a = new Animal();
if (a instanceof Dog) {
    ((Dog) a).bark();
} else {
    System.out.print("not a dog");
}

What is printed?

A
$ClassCastException$
B
$Compile-time error$
C
$not a dog$
check_circle
D
$Woof$

Explanation

The instanceof check prevents the unsafe cast. a is just an Animal, not a Dog.

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