How do I call the top ancestor method

Question

I have a class which inherits from a class which inherits from a class (and a few more in the original code :)).

How do I call from an override to one of the top most parents? Here is a code sample:

class Program
{
    static void Main(string[] args)
    {
        Animal a = new Animal();
        a.DoSomething();
        Predator p = new Predator();
        p.DoSomething();
        Cat c = new Cat();
        c.DoSomething();
    }
}

class Animal
{
    public virtual void DoSomething()
    {
        Console.WriteLine("Animal");
    }
}

class Predator : Animal
{
    public override void DoSomething()
    {
        Console.WriteLine("Predator");
    }
}

class Cat : Predator
{
    public override void DoSomething()
    {
        base.DoSomething();
        //Console.WriteLine("Cat");
    }
}

I want that when I call c.DoSomething() method I will get "Animal" as a result.

Thanks to all