using System;

public class Program

{

    public class ClasseBase

    {

        public virtual void Funcao()

        {

            Console.WriteLine("Base");

        }

    }

    public class Classe : ClasseBase

    {

        public override void Funcao()

        {

            Console.WriteLine("Derivada");

        }

    }

​

    public class Classe2 : ClasseBase

    {

        public new void Funcao()

        {

            Console.WriteLine("Derivada2");

        }

    }

    public static void Main()

    {

        Classe c1 = new Classe();

        Classe2 c2 = new Classe2();

        ClasseBase c3 = new Classe();

        ClasseBase c4 = new Classe2();

        c1.Funcao();

        c2.Funcao();

        c3.Funcao();

        c4.Funcao();

    }

}