下列代码的运行结果是：(     )

public class Animal {
    public String noise() {return "peep"; }
    public static void main(String[] args) {
        Animal animal = new Dog();
        Cat cat = (Cat)animal;
        System.out.println(cat.noise());
    }
}
class Dog extends Animal {
    public String noise() { return "bark"; }
}
class Cat extends Animal {
    public String noise() { return "meow";}
}