using System;

​

namespace ConsoleApplication1{

    public class ClassA

    {

        public ClassA()

        {

            Console.WriteLine("Object A");

        }

    }

    public class ClassB : ClassA

    {

        public ClassB()

        {

            Console.WriteLine("Object B");

        }

    }

    public class ClassC : ClassB

    {

        public ClassC()

        {

            Console.WriteLine("Object C");

        }

    }

    public class ClassD : ClassA

    {

        public ClassD()

        {

            Console.WriteLine("Object D");

        }

    }

​

    public class Program

    {

        public static void Main()

        {

            ClassC c = new ClassC();

            ClassD d = new ClassD();

        }

    }

}